Astro Pneumatic Tool 4901 0.401" Shank Super Duty Air Hammer with 5 Piece Chisel Set Maximum power industrial grade .401" shank air hammer for heavy duty, off-road, and automotive applications 5pcs 7" Chisel Set (Material: SCM440, 48-52 HRC) Storage case for air hammer, spring retainer and chisels Free Speed: 2000 BPM