DIN6887, ISO2492 Bonut Gibhead keys or tapered keys are made to BS46 Part 1: 1958 for imperial sizes and BS 4235 Part 1: 1972 for metric sizes, unless otherwise agreed with the customer, and are tapered on the top face that engages the hub. They are made from steel to BS907 Part 1 unless otherwise agreed. They are designed to be used on a shaft and hub assembly up to about 150mm diameter with pr..