Ed Brown Products Mainspring Housing 1911 Officers Smooth Blue. The perfect replacement for a cheap plastic housing in most factory pistols designed for carry use and based on an Officers sized frame. Also available with magwells in the magwell housing section. Internals not included may be purchase separately if needed. Specifications for Ed Brown Products 1911 Officer's Mainspring Housing: Manufacturer: Ed Brown Products Fabric/Material: Solid Steel Gun Make: Ed Brown Gun Model: 1911 Package Contents: Ed Brown Products 1911 Officer's Mainspring Housing What firearm models does the manufacturer say Ed Brown Products 1911 Officer's Mainspring Housing is compatible with? The manufacturer says that Ed Brown Products 1911 Officer's Mainspring Housing is compatible with 1911Ed Brown Products 816F-OF: Mainspring Housing 1911 Officers Smooth Blue