Dead blow hammers have a loose material, like shot, in a hollow head.  The shot increases the force of the blow and absorbs the energy, which reduces or eliminates recoil. Wiha Makes a great Dead Blow Hammer.  The steel handle version comes in 18oz, 21oz, 24oz, 30oz, 37oz, 49oz, 72oz, and 97oz sizes.  The Hickory handle version comes in 11oz, 16oz, 20oz, 26oz, 35oz, 44oz, 70oz, and 91oz sizes.  Wiha also makes a Dead Blow Sledge Hammer in 10lb and 15lb sizes with longer handles.  The hammer face is a medium hard polyurethane that preserves sensitive surfaces and they are replaceable.  At KC Tool, we have all 16 models of Wiha’s Dead Blow Hammer in stock and we sell them for less!