Features a square shoulder fulcrum pin of cold-formed heat-treated steel, which prevents pin rotation that can cause hole elongation and premature tool failure. Other quality features include: precision die-cast, high-strength aluminum alloy body, drop forged carbon steel upper handle. Thick cushion-molded vinyl grips for comfort. Sets up to 3/16" steel rivets and comes with four mounted nosepieces (3/32", 1/8", 5/32" and 3/16").