With the Tormek EzyLock, which is both a nut and a washer, you need no tools for mounting and dismounting the stone. The special pitch on the left hand thread causes the rotation of the wheel to tighten the nut to the correct torque. Turn the Ezylock counter-clockwise by hand and the grindstone will automatically tighten during the first sharpening. You won’t need any tools. When dismounting, you turn the stone clockwise and the EzyLock will automatically become loose.This construction makes it very easy to change grindstones on your T-7 Sharpening System (WC# 148103), from the standard aluminum oxide to the new specialty stones. The shaft, washer, and EzyLock are all constructed of stainless steel.Using genuine Tormek replacement parts ensures the life of your Tormek tools.