More Body: It can extend the length of the router bit body and make your woodworking projects more flexible to reduce costs and improve efficiency. Rigid Alloy: It adopts hard alloy, with high rigidity and strong strength, long lasting. Powerful Clamping Force: With extremely powerful clamping force to ensure stability when using. Application: Used for various machining applications, including boring, milling, reaming, tapping and grinding. Content: 1 x 1/4 Inch Router Collet Extension, 1 x 1/2 Inch Router Collet Extension, 1 x 8mm Router Collet Extension.