Fiskars IsoCore 20 oz General Use Hammer 13.5 Inch Ideal for driving nails during a wide variety of common tasks on the job site or around the house Patented IsoCore Shock Control System absorbs strike shock and vibration to reduce the punishment your body takes, transferring 4X less shock and vibration than wood handles Insulation sleeve captures initial strike shock before it can reach your hand Dual-layer handle features a specially formulated combination of insulating materials to dampen lingering vibration Full lifetime warranty