The Hogue Aluminum Mainspring Housing is precision machined from solid billet stock Aerospace grade 6061 T6 aluminum. Carefully engineered and sized for ultimate fit, form and function, the Hogue Aluminum Mainspring Housing is perfect for dressing up or customizing your prized 1911. Specifications: - Fits: 1911 Officer - Profile: Flat, Checkered, Aluminum - Color: Matte Black