Nupla's Nupla-Cast Urethane Extreme Power Drive Dead Blow Hammer has patented shotloaded composite interior cavities encased in a tough polymer out jacket, offering 40 percent more driving power and less rebound. The Blow Hammer line isfeatures 100 percent cat polyurethane faces, are designed to withstand sever striking applications and offer genuine Nuplaglas Lifetime fiberglass handles. The entire line is available in a wide range of weights and ergonomic grip designs and is also available in non-sparking and non-magnetic versions.