Deadblow Hammer
From RitchieWiki
A deadblow hammer is a hammer designed to absorb the rebound of a strike. The inside of the hammer is equipped with a chamber filled with sand, steel, or other non-sparking metal. It is the loose material inside the chamber that helps to reduce the impact of bouncing on contact. Most deadblow hammers are made from plastic and range in size from eight ounces (227 g) to 12 pounds (5.4 kg).[1]
