12 Piece, Jumbo Hex Key Set, Sets Consists Of: Metric Sizes: 8mm, 10mm, 12mm, 14mm, 17mm & 19mm, SAE Sizes: 3/8", 7/16", 1/2", 9/16", 5/8" & 3/4", Includes Blow Mold Storage Case, Heat Treated, Chrome Vanadium Steel, Black Oxide Finish Resists Rust & Corrosion, Ideal For Use On Large Machinery.