Features and Benefits: Made of industrial grade chrome molybdenum (chrome-moly) steel alloy; Each impact socket comes with protective sleeve; Blow molded case for easy storage and transport; Sizes: 17 mm x 19 mm; 3/4 in. x 13/16 in.; 7/8 in. x 21 mm and a 3 in. extension bar; This is a Flip Impact Socket Set. It has 4 Pieces. Sockets are 1/2 in. Drive and Thin Wall design.
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