The indexing head is a machine tool accessory which is installed on the milling machine to divide the workpiece into any equal parts. The indexing ring and vernier are used to locate the pin, the indexing disk and the exchange gear. The workpiece clamped between the apex and the chuck is divided into any equal parts. The auxiliary machine tool uses different shapes of cutters to carry out various grooves, spur gears and helical spur gears. Machining of Archimedes spiral cam, etc.