Eliminates the guesswork and gives an accurate, repeatable method to achieve a crisp, clean-breaking trigger pull on semi-automatic firearms. Individual, easy-to-change Adapters attach to a precision-ground indexing elevator column and clamps the hammer in the right position for correct stoning with the specially ground Series II India Stone. Adjustable design lets you change hammer angle to meet the shooters' precise needs. Series II India Stone required for use. Purchase separately. Universal Adapter (described below) adds incredible versatility. SPECS: Steel, blued, precision ground and hardened. 5" (12.7cm) 4" (10cm) high, 3" (7.6cm) wide. Fixture i Mfg: Power Custom