This flat mainspring housing is designed specifically for 1911 pistols and features precision 25 LPI checkering for enhanced grip texture.1911 Mainspring Housing - Flat Profile25 LPI (Lines Per Inch) checkering patternBlue finish for durability and corrosion resistanceCompatible with Government/Commander 1911 framesProfessional gunsmithing componentEssential for 1911 builds repairs or customization projects providing reliable spring tension and improved grip control with its textured checkering pattern.