Thick, heavy gauge metal is aluminized for longevity, strength, and the unique Flowmaster sound.

No glass packing inside to wear out, retain corrosive moisture or cause undue flow restriction.

Scavenging effect reduces underhood engine heat, further increasing performance.

Specific dyno tested plate placements available for a variety of applications, including Racing, Towing, Recreation, Marine, and MORE!

"Dead-End" one-way tube absorbs high frequency pitches and transfers the resonant vibrations to the thick, metal case, thereby deadening the sound, much like a hand muffling the chime of a dinner bell.

Sealed hollow chamber is "tuned" to absorb mid range resonant frequencies, thus only hard to hear, low "bass" frequencies remain, giving the Flowmaster it's distinctive, deep  tone, without restricting flow

Main Chamber allows flow around the baffles, creating a low pressure area, thus resulting in a vacuum pulse to "grab", or scavenge exhaust pressure pulses and pull them down the pipe from the cylinder heads... Almost like blowing over the top of a full soda bottle.

Final Chamber "catches" back pressure pulses, further reducing restriction

Glass Packs, or straight thru mufflers, have been in use for years. The characteristic high pitched "rap" of this tubular compact muffler, is far from being an "unrestrictive straight through" muffler. Taking a look at the internals of a typical glass pack muffler, you can see the turbulent obstacles and restrictive passages the exhaust has to battle against… usually a losing battle.