Forged from the finest chrome molybdenum alloy steel - the best choice for strength and durability. Radius corner design - to extend the life of fasteners. Ideal for working in tight areas. Included in a heavy duty blow molded case. Fully guaranteed No doubt, Sunex tools offer one of the most complete and toughest Impact Socket lines around. This 1/2" drive, deep thin wall flip impact socket set is designed to tackle the toughest jobs with solid durability and keeps them pounding job after job. Also each socket features a radius corner design, causing the socket to grab the sturdy wall of the fastener instead of grabbing the corners, resulting in less wear on the fastener. Set includes: 3/4" x 13/16", 7/8" x 15/16", 19mm x 21mm flip sockets; and a 3" socket extension.