High-quality for hex - Allen screw fasteners in Metric sizes annealed & tempered S2 tool grade steel resists twisting and cam-out. in Taiwan Must-have set for automotive vehicle, bike, appliance repair - especially with increasingly-common Metric-sized screws & bolts Hex shank fits all 1/4-inch driver handles, extensions & adapters Sizes 1.5 mm, 2 mm, 2.5 mm, 3 mm, 4 mm, 5 mm, 5.5 mm, 6 mm & 8 mm in PVC organizer sleeve .