3-1/2" Heavy-Duty Pistol Grip Air Hammer Kit The 7150K 3-1/2” Heavy-Duty Pistol Grip Air Hammer Kit with Chisels is the most powerful air hammer in its class with an excellent power-to-weight ratio. Standard 0.401 round shank. Longer piston stroke for added power. Integral muffler minimizes exhaust sound. Five popular chisels included for a variety of applications. Kit includes:. 3-1/2” Heavy-Duty Pistol Grip Air Hammer – 7150. (5) Assorted Chisels. Standard 0.401 Round Shank. Easy Change Retainer. Spring 7150K Yes -