This Cylinder & Slide 1911 Ultra Light Speed II Chamfered Hammer Set contains the Ultra Light Speed II Hammer, Ultra Low Mass Sear and Match Disconnector. All parts are heat treated to 50-54 RC. This set is for the 1911 race gun builder who wants an ULTRA LIGHT hammer weight for the fastest lock time with a hammer with a thumb cocking piece and any trigger pull weight that they are capable of producing. Suitable only for match competition 1911 pistols.