Foredom Special Use Hand Piece 15 The #15 is a hammer hand piece with a reciprocating rather than rotary action and is used at low speed (0 to 5,000 RPM) and only in forward rotation by jewelers for stone setting and decorative work. The hammer has a 1/32" stroke and its impact force can be adjusted from light to heavy by rotating the adjusting ring. It requires periodic lubrication with 10005 hand piece lube. It is supplied with the HP10177 anvil point and pin for installing and tightening. See accessories for optional pave point and carbide stylus etc. Dimensions: 6 1⁄4" x 1⁄4" diameter at tip. Available as the basic hand piece or with the added duplex joint. The duplex joint / duplex spring provides extra flexibility to the hand piece when more precise control for delicate work is required. Duplex joint hand pieces are not covered under warranty.