Composite Air Hammer High performance and low weight. Multi-patented muffler/exhaust system gives this tool and extremely low noise of 88 dBA and vibration level of 4.2 m/s. Sheer power of 3,000 Blows per minute makes this the strongest hard hitting air hammer on the market. High quality safety-lock retainer for ease of chisel change and added safety. Specifications . Shank Opening - .401”. Retainer – Safety-lock. Valve – Plate. Weight (lbs) – 3.3. Length(in) – 7.6. Air Cons. (CFM) – 6. Rec. Hose Size (in.) – 3/8. Air Inlet (in.) – 1/4 NPT 5100-A-T Yes - LEAD