The Shooters Design 5 Inch Steel Outer Barrel is made for use with the TM Hi-Capa 5.1 and is only compatible with a Shooters Design Compensator. This barrel is very well made from stainless steel for a robust build that will not corrode. On top of the chamber Shooters Design have etched "S.A. 45AUTO DANGER EXHAUST PORTS READ MANUAL" for added realism. This barrel is a must if you purchase Shooters Design slide and compensator kit; this barrel will only work with Shooters Design compensator. This is a great upgrade for those looking for more authenticity and a better build quality for their race pistol.