A spline bore head is a specific type of head that comes on a bore gauge. A bore gauge is a precision measurement tool used to measure holes. A spline is a key shape that fits into a grooved wheel shaft. A spline bore head gauge includes both go and no-go plug gauges and comes with grooved parts. A spline bore head is typically designed with both actual and effective tolerance in mind. Knowing the usability of a spline bore head is important when selecting one. In terms of general upkeep for a spline bore head, it is important to conduct wear tests to assess the resistance and wear tolerance. Spline bore heads can be built for internal or external splines, as well as with 2- or 3-point heads.