Custom Quality Checkering for Improved Grip, Rounded Heel for Enhanced Carry and Shooting Comfort, Machined from Tough Premium Barstock Custom quality 1911 mainspring housings precision machined from tough, solid barstock to stand up to prolonged, heavy use. Machined to maximum tolerances for a snug, drop in fit in most 1911 pistols, which eliminates unsightly gaps and improves performance. Checkering is precision cut by master metalsmith Pete Single, and meets or exceeds that found on the very finest custom 1911 pistols. Perfectly formed diamonds provide a locked-in grip on your pistol to aid in control of the pistol during rapid fire. Available in 20, 25, and 30 lines per in Mfg: Stan Chen Customs SPECS: Steel, blued chrome-moly 4140 (Blue), or 416 stainless (SS). Fits Government and Commander model 1911 pistols. Drop in fit for original government spec 1911 frames, however minor fitting may be required in some pistols.