Taper lock bushing dimensions are described by 4 digits symbolizing two figures. The first two digits symbolize the maximum bore diameter and the final two digits signify the bushing duration. For example, component variety 1008 has a highest ID of 1." and an ID dimension of .8" inches, with the overall duration specified as a entire number of inches adopted by a portion. For instance, a 1.5" diameter gap would be 1-1/2. Metric gap measurements are indicated by "MM" soon after the metric measurement (X 25MM). Effortless to install and eliminate, these bushings fit on tapered bushing sprockets, or pulley. Bushing touches and wedges inwards, clamping sprocket shaft and bore. Bushing has an 8° taper and is made of steel with a black oxide coating.