Features: This convenient ring stretcher quickly and efficiently stretches and enlarges rings and bands. It's and portable, so you can work anywhere in the world with ease. Ring Stretcher: This ferrule is made of hardened stainless steel. It consists of three parts: a tapered pin expander, a collet multi-stage mandrel and a nylon mold. Usage: Used for stretching all soft precious metals such as silver, gold, and copper. Great for woodworking, construction, engineering, jewelry and metal shaping. Function: First place the ring on the stepped chuck, select the suitable size for the ring, and then place the expansion clamp on the base. Then insert the tapered pin rod and tap the top lightly with a hammer. Simply wipe the other end to remove the mandrel. Dimensions: This ring stretcher tool has a ring size capacity of 6 or larger, base inner rod size: approximately 6-1/2 inches.