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Flowmaster Original 40 Series Mufflers Customer Reviews

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61 Customer Reviews

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Customer Reviews

Flowmaster Muffler 40 Series American Thunder

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Reviewed by Jeremy A (Monroe, LA) Reviewed for a 2001 Ford Ranger — 2007-02-13 05:25:48

I got just what I expected. The sound is awesome. You can't beat the Flowmaster sound.

What a deal

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Reviewed by G S (The Rock, GA) — 2012-12-28 08:52:03

Best price anywhere shipped really fast for free . Thanks Autoanything

Adds "Thunder" to your truck

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Reviewed by Erik S (Shiner, TX) Reviewed for a 2006 Ford F-150 — 2010-02-23 17:04:46

Put it on my 4.2L v6 Ford F-150 and it makes it sound like I got a v8 under the hood. Absolutely love the deep tone and sounds great at start up and high RPMs. I did the installation with a friend and it was pretty easy. Not sure about my mpg yet because I havent let off the gas pedal. If you want to add some muscle to your truck and extra HP this is a product that will do it.

great product even better service

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Reviewed by Beau G (Woodlawn, TN) Reviewed for a 2000 Chevy Silverado — 2008-03-29 16:52:13

still the best sound and quality we all know and love. first tike autoanything user, they just got my business for a lifetime. thanks fast delivery, great service.

flowmaster 40

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Reviewed by sean m (Valrico, FL) Reviewed for a 2004 Ford F150 — 2007-03-13 10:52:58

i put this muffler on my 04 f150 4.6, sounds great. Gets fairly loud. I suggest letting some one drive your ride while you watch so you can really give the exhaust a rating.

my thunder

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Reviewed by hank s (Harrison, OH) Reviewed for a 2003 Ford F-150 — 2008-04-10 06:39:11

the flowmaster gives my truck the sound that turns heads when i go by. it also gives it a few more horses, its a great product that i have used on my trucks for years. I highly recommend auto anything for your purchases and the flowmaster thunder for your vehicle. regards hank

What a Sound!

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Reviewed by Rick M (Centralia, WA) Reviewed for a 1970 Plymouth Roadrunner — 2008-07-02 06:40:05

I installed the 40 Series with an X pipe on my 70 Roadrunner.It gives the term "American Muscle" a new meaning.What a sound.One of the best investments I made for my Roadrunner.You guys really came thru.Thanks,Rick

98 Dodge Ram 1500

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Reviewed by Theresa C (New Milford, CT) Reviewed for a 1998 Dodge Ram — 2006-09-26 15:14:17

Half hour installation, excellent sound. Great product, would highly recommend it to anyone.

2006 F150

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Reviewed by Christopher R (Belmont, ME) Reviewed for a 2006 Ford F-150 — 2008-04-02 12:59:14

I installed my Flowmaster on a 2006 F150 4X4 5.4L Champions Editoin. It sounds sweet,good rumble,deep tone & when you lug the motor a little it gets super deep toned. I would highly recommend this for anyone looking for a not to over bearing sound.

08 GMC SIERRA

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Reviewed by Garret B (Nottingham, MD) Reviewed for a 2008 GMC Sierra — 2008-08-15 14:15:53

This flowmaster opened up a little more hp and gave me that beautiful flowmaster sound at take off and on through the gears. The only down fall would be the "brown note" when just cruising at highway speeds in overdrive. If you are a daily driver of long distances you might want a little less cab noise. As far as install I kept the passenger side(stock) pipe and bent/fabricated a drivers pipe to match. It took me about 3 hours to bend, weld and hang.

Outstanding Muffler

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Reviewed by Melanie H (Acworth, GA) — 2005-12-27 16:10:30

I am very happy with my Flowmaster Muffler 40 Series American Thunder. The sound is better than i expected and the installation was so easy. I highly recomend this muffler for any application.

Bettewr sound than stock and better mpg

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Reviewed by Amey K (Midland, GA) — 2008-03-14 17:19:02

I found that the flowmaster provided a nice rumble during low rpm's and was quite during highway speeds. After the initial reving and constant lead foot to hear the exhaust, when driven under the same conditions as stock muffer, will, on average, yield more mpg.

Brings back the days of old

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Reviewed by charles p (Bronx, NY) Reviewed for a 1980 Chevy Van — 2009-03-23 21:07:02

My current project of restoring a 1980 Chevy Van has been an enjoyable experience. Now with all of the mechanical restoration complete. I wanted to give the van a real feel of the type of exhaust system a small block chevy should have. The custom ordered exhaust along with the classic "Flowmaster 40" Mufflers completed this task. Wow what an improvement in overall output performance as well as that classic "Street Rod" sound.

Awesome Sound

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Reviewed by Antonio O (Shawnee, OK) Reviewed for a 1999 Ford F150 — 2007-03-26 19:31:03

Very pleased with the sound, and extra gas mileage about 60 more miles on a tank of gas.

excellent exhaust

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Reviewed by lisa m (Brunswick, GA) Reviewed for a 1992 GMC Jimmy — 2010-02-21 17:36:37

I love the sound of the exhaust i have tried many different name brands and the flowmaster is the best overall muffler and was the cheapest that i found online threw autoanything i will order a couple more for my other vehicles im building thanks

Opinion on muffler.

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Reviewed by Steven H (Otway, OH) — 2006-08-07 21:46:56

This muffler has a deep high performance, throaty sound. It is very great and I am extremely happy with it.

Flowmaster

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Reviewed by Aaron H (Spring Creek, NV) Reviewed for a 1988 Ford F-150 — 2008-04-26 11:41:21

It has increases horsepower and throttle response. I hollowed out my catalytic converters first though. The flowmaster has a great sound to it.

awsome

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Reviewed by travis d (Waskish, MN) Reviewed for a 1996 Chevy S10 Pickup — 2008-04-23 19:14:46

i instaled the muffler in about 30 min. has good sound and gave me a noticable increase power. also gave me about 2 mpg better gas milage. will buy again for next truck.

flowmaster mufflers

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Reviewed by bob c (Campbellsville, KY) Reviewed for a 1955 Ford F-100 — 2008-05-07 18:09:06

excellent product and fast shipping.

great product

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Reviewed by Brandon K (Annapolis, MD) Reviewed for a 2006 Nissan Titan — 2008-07-31 12:36:26

great sound both inside and out. great muffler

Flowmaster

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Reviewed by Zachary M (Goshen, CT) Reviewed for a 2007 Toyota Tacoma — 2008-10-09 18:02:44

I love my Flowmaster 40 Series American Thunder. I installed it on my Ford Ranger pick up truck and it sounds amazing. I love the deep sound and power gains from it. I initially had a factory muffler and the sound and restrictive baffling caused my motor to struggle. Thank you Flowmaster.

Flowmaster 40 American Thunder

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Reviewed by Monty Y (Placentia, CA) — 2007-11-16 17:24:50

The muffler was shipped promptly. It does give my 3.7l Dakota a beefier sound but not as loud as some say it is... maybe that just because I only installed the muffler and tip without pipes or anything. All in all a great buy.

8.1liter/ 40 series muffler

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Reviewed by john f (Corvallis, MT) Reviewed for a 2002 — 2006-03-12 23:55:36

My new 40 series flowmaster souds awesome on my 8.1 liter chevy avalanche, deep powerful aggresive tone doesnt get any better.

American THUNDER!

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Reviewed by Matthew N (El Paso, TX) — 2006-10-09 22:40:48

Perfect sound, deep and powerful and not annoying. Definate gains in gas mileage and horse power! Noticed around 20-30 extra miles to my tank, was not expecting such a high increase! Will buy another for dual exhaust!

One word: badass!!

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Reviewed by Dan D (South Burlington, VT) Reviewed for a 2003 Chevy Silverado — 2007-04-27 20:30:11

I hooked up a single 3" in, duel 2.5" out muffler with 3 inch chrome tips and it sounds greater than I ever imagined. I've started a new trend at college. I've heard them on the internet, but since I have them on my truck, i still can't get over the deep throaty sound! When I leave, people know it! Now that the system is broken in the tone is just immense! I have gotten better gas milage and acceleration too! I only use and 1/8 of a tank to go 50-60 miles to school now, instead of a 1/4 tank. And I have a 2003 silverado 1500 with a 327 vortec. The interior sound is a little lound when shifting from 1st to 2nd but after that you just her a rumble. There is a drone at 65 mph and on, but not too bad. Again, I can't say enough about my flows!

sounds great

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Reviewed by Joshua M (Ellsworth AFB, SD) Reviewed for a 2004 Chevy Tahoe — 2008-03-27 09:55:00

Definitely was worth getting this muffler. Made my Tahoe sound like it actually has a v8. Only have the 4.8 engine, but it still has that v8 growl to it with just installling the 40 series muffler. Guys I work with have commented on how good it sounds. One of them has a 40 series on his gmc canyon. I would definitely recommend this muffler to anyone thinking about getting it. Only cost me $50 to get it installed at an exhaust shop in town.

Great muffler!

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Reviewed by Cody H (Buhl, ID) Reviewed for a 2000 Chevy Silverado — 2009-01-09 13:11:22

Sounds great, boosts power, gained almost a mile per gallon. Well worth the money for the Flowmaster quality.

very pleased

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Reviewed by George O (Yuma, AZ) Reviewed for a 2007 Dodge Ram — 2009-08-28 14:15:12

paid meineke for installation. muffler is great improved HP and Mileage and sounds great.

flowmaster muffler

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Reviewed by Chris T (Logan, OH) Reviewed for a 2011 Dodge Ram — 2012-04-11 04:28:59

What a difference this muffler makes. My Dodge sounds great!!

SOUND PERFESTION

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Reviewed by Mike B (Peoria, AZ) — 2007-04-11 08:19:40

IT HAS THE SOUND I WAS LOOKING FOR.ON MY CORVETTE 6 SPEED. AND I WILL ADD,A VERY GOOD PRICE.THANKS, MIKE

AWESOME SOUND !!!!!!!!!!!!!!!!

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Reviewed by tonya h (pekin, IN) Reviewed for a 1995 GMC C/K 1500 — 2012-07-29 18:37:35

GREAT PRODUCT COULD NOT BE MORE PLEASED

1998 Durango

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Reviewed by Nicholas O (South Portland, ME) Reviewed for a 1998 Dodge Durango — 2009-03-10 05:25:44

Installed it on my 1998 durango 5.2L and it brought it to life. Nice deep tone. Love it. Works great, ecpecially cause exhaust is already 2.5in.

american thunder

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Reviewed by Edna F (Glendale, CA) Reviewed for a 2002 Ford F350 — 2008-02-12 22:59:49

great deep sound. deep mumble.

Flowmaster Mufflers 40 Series American Thunder

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Reviewed by Steve S (Marietta, OH) Reviewed for a 1995 — 2005-12-24 06:04:39

It is worth every penny

99 durango 5.9l 360

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Reviewed by dawn m (Kenosha, WI) Reviewed for a 1999 Dodge Durango — 2009-04-11 10:22:45

this muffler sounds great on the truck. i like the sound better if i dont connect the tailpipe to the muffler. but ive got to so its not toooo loud. it has a nice rumble when yhou are full throttle and let off the gas. i love that. very great sound over all. if you do get this muffler try to find a way to mount it as far back as you can in the exhuast system. better sound IMO.

Flow

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Reviewed by Rhonda H (VILLA PARK, CA) — 2012-09-28 14:43:50

I love these mufflers. They make my 1968 F250 ranger sound deep and throaty. Thanks Flowmaster for designing a great product

Mean sound!

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Reviewed by Jackson B (Merritt Island, FL) — 2008-12-30 08:22:35

Just put this puppy in my '98 v6 3.0 Ranger and it sounds mean. Got the 2.5" pipes, gutted the cats and now people think i got a V8 under the hood. Not only sound, I can notice a more responsive throttle, and quicker acceleration. Great pipe, but the price on AutoAnything is not the best. Could of bought these pipes at a local Auto Zone for $72 with tax. Owell.

Flowmaster Muffler-Review

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Reviewed by Jordan A (Libertyville, IL) Reviewed for a 2003 Chevy Silverado — 2012-01-13 06:22:46

Easy to install and sounds great!!

40 Series

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Reviewed by Ian M (Sedgwick, KS) Reviewed for a 1999 Pontiac Firebird — 2011-07-10 03:32:48

Love the sound of my 40 series. I put it on my 99 Trans Am. Sounds great and turns heads. Love it.

THE BEST SOUND FOR MUSTANGS

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Reviewed by Christopher K (Scranton, PA) Reviewed for a 1989 Ford Mustang — 2009-01-20 01:05:53

These are the best sounding mufflers for a mustang. I switched from Warlocks, and i cant believe how much better they sound....A+ Rating

40 series on TrailBlazer

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Reviewed by Emmanuel P (Aurora, IL) — 2011-07-01 07:19:02

It sounds very good and mean it lives to its name american thunder

wicked product

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Reviewed by Dylan S (Aurora, CO) Reviewed for a 2000 Toyota Tacoma — 2008-10-04 05:56:13

Very loud and aggressive, especially if i hover around 2100 rpm. however very little cab noise (with windows up). it's got a head turning growl and i just love that start-up roar. very nice. very pleased. only thing is is that i had to weld the muffler in sideways a quite a bit because it didn't even come with the option for center inlet/outlet. settled for a offset/in and center/out. love it though.

2011 F-150 5.0L

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Reviewed by David W (Waukesha, WI) Reviewed for a 2011 Ford F-150 — 2012-01-16 06:39:49

This is by far the best sound that I could have wanted from any muffler.. I have used Flowmaster products in the past & have never been disapointed!! It gave my truck a real musclular sound.. It now sounds like the tough truck that it is..

flowmaster

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Reviewed by Andrea C (Independence, MO) Reviewed for a 2003 Chevy C/K 1500 — 2011-04-28 14:06:49

the prices at auto anything are the best that ive found

very impressive sound

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Reviewed by Richard L (Kewaunee, WI) Reviewed for a 1989 Chevy C/K 1500 — 2007-08-22 12:48:22

Awsome low range sound,and fairly quiet at hiway speed. great product!

thunder

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Reviewed by FREDERICK W (HOUSTON, TX) Reviewed for a 2006 Ford F-150 — 2011-04-29 07:40:24

Its tha best sound i ever heard

Great sound.

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Reviewed by Damon W (Brown City, MI) — 2011-05-23 07:44:05

The flowmaster I bought have a good deep throaty sound. Very pleased with the quality and sound of these mufflers.

2007 silverado 2500 HD

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Reviewed by scott g (Midlothian, TX) Reviewed for a 2007 Chevy Silverado — 2010-02-19 21:01:34

love the way my truck sounds,also bumped up my fuel mileage great product!!!!

Love it!!

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Reviewed by David S (Millersburg, PA) Reviewed for a 2010 Ford F-150 — 2011-06-30 18:11:05

This is my third flowmaster system on 3 vechiles from a 90 ranger, to a 99 f150 to a 2010 f150 love them all. Keep up the great work. Installed on a 4.6L dual out sounds awesome very deep rumble.

Jeeps are GREAT!!

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Reviewed by Ronald G (Yaphank, NY) Reviewed for a 2007 Jeep Wrangler — 2010-03-17 17:35:06

V6 TO A V8 THE SOUND WAS GREAT easy installation for the price it was a GREAT buy!

THE SOUND

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Reviewed by Steve K (Helena, MT) Reviewed for a 1998 Dodge Dakota — 2007-11-01 06:09:37

Sounds good. Deep and Mellow. Easy to instal.

Truly American THUNDER!

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Reviewed by Samuel V (Ocean Pines, MD) Reviewed for a 2000 Ford Expedition — 2006-06-23 19:05:48

Great replacement for the hum-drum stock mufflers. With my 5.4l, this tube rocks my Expediton. WOW!

40 Series

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Reviewed by Paul C (Phoenix, NY) — 2006-06-14 04:50:18

Happy w/ the sound and real easy to install.

Nice muffler, wrong truck

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Reviewed by John H (New Boston, TX) Reviewed for a 2006 Chevy Colorado — 2012-07-17 19:56:13

Installed this muffler on my 2006 3.5 Colorado I5. Good solid quality product that fit perfectly, it just doesn't sound very good on my inline 5 cylinder. It is a muffler that keeps in-cab resonance to a very comfortable level and is not a very loud muffler if you keep the rear cat in place. It would probably sound great on a V8 if you wanted to keep in-cab noise comfortable and not have your vehicle obnoxiously loud. Sounds really nice while idling, but when rpms get higher on my 5 cylinder, it sounds like a riceburner :P

Flow and Go

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Reviewed by Craig W (Louisburg, KS) Reviewed for a 1995 Dodge Ram — 2006-02-15 06:56:03

The flowmaster 40 series was for my son's truck. He was very happy with the results and also the very fast turn around time on this order.

97 Dodge Dakota

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Reviewed by Justin G (Sussex, NJ) Reviewed for a 1997 Dodge Dakota — 2007-01-03 19:03:00

Excellent muffler. Great sound, installed in twenty minutes. Great results and performance. Would recommend it to anyone looking for performance and deep sound.

F150 With flowmaster

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Reviewed by Eugene Z (NORRISTOWN, PA) Reviewed for a 2007 Ford F-150 — 2011-09-09 03:47:29

Muffler has a good sound, however I thought it would be a little louder. Think I'm gonna buy some high flow cats. I'll let you know what its like then!

First time buyer

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Reviewed by joshua g (New Haven, CT) — 2008-06-28 17:32:57

I was a little nervous about getting the loudest one but its sounds awsome, even with a little 4 banger like mine. though i should have measured the exaust pipe before order. the welding job the guys at monroe did is adequate but could have been better.

2007 chevy avalanche 3 INCHES IN AND DUAL 2.5 INCHES OUT.

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Reviewed by christopher p (Spring Hill, FL) Reviewed for a 2007 Chevy Avalanche — 2009-02-07 16:23:19

I HAD MY 40 SERIES WELD ON AT A LOCAL MECHANICS SHOP, BUT INSTALATION WAS STRAIGHT FOWARD. I LIKE THE SOUND, BUT I THOUGHT IT WOULD BE LOUDER THAN IT WAS. NEXT FLOWMASTER WILL HAVE TO BE A RACE 40 SERIES. I DIDNT NOTICE ANY PERFORMANCE DIFFERENCE EITHER, DONT KNOW IF I WAS SUPPOSE TO THOUGH. OVER ALL WORTH THE 80 BUCKS I SPENT.

Better performance, but pretty quiet

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Reviewed by Ryan N (Spanaway, WA) Reviewed for a 1990 Ford F-250 — 2009-06-10 20:13:05

I can definitely feel a difference in the acceleration, but for my engine it is pretty quiet. I was hoping for it to be a little more throaty. I have a 302 engine, and it has a big cat converter, so there isn't much push. I would recommend it for big blocks.

alright

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Reviewed by Brandon A (Littleton, CO) Reviewed for a 2001 — 2006-03-27 22:43:18

its alright i thought it would b louder but its not i wish it was