Hex Keys is Made of Chrome Vanadium Steel (Better strength than carbon steel), with a Black Oxide Surface After Heat Treatment, Which is Durable. Allen wrench set includes Metric 9 Pcs: 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10mm and SAE sizes 9 Pcs: 5/64, 3/32, 1/8, 5/32, 3/16, 7/32，1/4, 5/16, 3/8 inches. Ball & Flat Head Design ultra-long arm for greater access to tight spaces.A ball end that allows a 25-degree offset to reach positions faster.  The t-handle offer force application while loading and unloading fasteners. additional advantages for increased reach and torque, ensure effortless and efficient use. Color-coded Handle Bright-bold color coding for quick and easy identification.Each hex key is clearly size-marking for easy selection. GURADESIGN 19-Piece Allen Wrenches Set, Hex Key Set,Metric and SAE Allen Key Set Extra Long with Ball End T-Handle, MM(1.5mm-10mm),SAE(1/16"-3/8") Chrome Vanadium Steel