Taparia KI 10V Steel Allen Key Set (Black Finish, Box Packing, Pack of 10) Allen Keys are made from special grade Alloy steel which withstands up to 30 Percent higher Torque as compared to Allen Keys made from CrV Steel. Higher hardness of 57 to 62 HRC offered in case of Brown Allen Keys along with superior steel properties enables up to 30 Percent higher wear resistance. Allen Keys are aesthetically good looking. Applications: Can be used on 1) Common machine parts 2) Bicycle maintenance 3)Professional Home Appliance Maintenance.