Price: $46.14

MagnaFlow Glass Pack Straight-Through Muffler - Universal - Aluminized Steel - Satin Finish

Item # MF18129

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magnaflow mufflers 4 round x 22 long inch gas engine glass pack straight-through muffler - universal aluminized steel satin finish

  • 3 Inch Inlet Diameter
  • MagnaFlow
  • 18 Inch Body Length
  • 3 Inch Outlet Diameter
  • Gas Engine
  • 4 Round x 22 Long Inch
  • Satin Finish
  • Round
3" Inlet/outlet; 4" diameter x 22" long. Achieve the classic glass pack sound without the burnout common to fiberglass-packed mufflers. Basalt rock wool surrounds a straight-through core, which enhances engine performance. Fastest Shipping and Guaranteed Lowest Prices for MagnaFlow Glass Pack Straight-Through Muffler - Universal - Aluminized Steel - Satin Finish. Read our customer reviews of MagnaFlow mufflers. Call 800-298-8924 for expert service or order your mufflers part number MF18129 by MagnaFlow online at

MagnaFlow Mufflers - MF18129

3" Inlet/outlet; 4" diameter x 22" long. Achieve the classic glass pack sound without the burnout common to fiberglass-packed mufflers. Basalt rock wool surrounds a straight-through core, which enhances engine performance.


  • Glass pack muffler produces lasting, vintage sound unlike that of any modern muffler on the market
    • Tightly packed basalt rock wool and aluminized steel mesh insulate the core to absorb high-frequency exhaust noise
      • Creates that classic glass pack rumble
  • Innovative basalt rock wool packing material outlasts fiberglass, which can burn out over time
    • Prevents sound degradation even with extended use
    • Protects from high exhaust temperatures and prevent blowouts
  • Straight-through design enhances exhaust flow, thereby increasing horsepower, torque and fuel efficiency and improving engine performance
    • Perforated core runs a direct route from inlet to outlet
    • Unique design excludes baffles, chambers and louvers, all of which impede airflow
  • Robotic CNC welding is unsurpassed for precise construction - prevents distortion and cracking
  • Aluminized steel with satin finish resists corrosion
  • Reversible muffler functions in both directions - can be flipped around for custom installation
  • Made in the USA


  • Muffler shape: round
  • Overall dimensions: 4" diameter x 22" long
    • Body length: 18"
  • Inlet/outlet diameter: 3"
  • Inlet/outlet position: center/center
  • Core diameter: 2-1/2"
  • Welding required for installation
  • Lifetime warranty

This MagnaFlow muffler produces the classic rumble that's typical of a glass pack, but this glass pack muffler won't burn out over time. Traditional glass packs are insulated with fiberglass, which has a reputation for melting after extended use. When the fiberglass melts, the muffler loses its ability to cancel exhaust noise, and it functions more like a straight pipe.

This muffler, however, features a straight-through core that is insulated with basalt rock wool, which not only absorbs high-frequency exhaust noise the same way fiberglass does, but also stands up to high exhaust temperatures over time. Furthermore, the muffler body is precision machined using robotic CNC welding, which prevents distortion and cracking, thereby extending the life of your muffler. It's the ideal muffler for your hot rod or for any high-performance vehicle.

Internal muffler diagram of aluminized steel, perforated core surrounded by mesh and basalt rock wool acoustic fiber

A. This muffler's aluminized steel, perforated core runs directly from the inlet to the outlet, allowing exhaust gases to pass through without restriction. It contains no baffles, chambers or louvers, which would restrict airflow. When air flows unimpeded through the exhaust system, horsepower, torque and fuel efficiency increase. These increases lead to improved engine performance.

B. and C. To regulate exhaust noise, tightly packed layers of aluminized steel mesh (B) and basalt rock wool acoustic fiber (C) insulate the core. These materials absorb high-frequency sound waves to produce classic glass pack rumble, shield high exhaust temperatures and prevent hazardous blowouts.

D. Using robotic, CNC welding, the inlets and outlets are machined for precise, durable construction that eliminates distortion and cracking.

E. All components are made of aluminized steel with a satin finish, making this muffler corrosion resistant.

18129 MagnaFlow Aluminized Steel Universal Glasspack Muffler - Round Shape


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    Written by:
    Lindsey S
    Edited By:
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