This is a Fusion Pro-Series, Stainless steel extended slide stop for 1911 style Colt pistols, 45 acp with Matte finish. Precision machined CNC from 17-4 PH Stainless Bar Stock & heat treated. Will work with all 1911 Colt style pistols, models and sizes. This is a high grade Professional Gunsmithing part. Made in the USA.