The Big Horn® 1/4" Router Collet is an aftermarket replacement for the Porter-Cable 42999. This router collet is designed for use with the 7518, 7529, 690 and 890 series of Porter-Cable Routers. Its clever design allows the router bit, collet and collet nut to be removed as a single, unified unit, which helps prevent lost bits and aids in removal of stuck or immovable bits that won’t budge. Features: Aftermarket replacement for the Porter-Cable 42999 For use with 1/4" shank router bits Replace lost router collets Designed to minimize bit run-out and enhanced robustness Router collet and nut are one unit with an Auto-Release design that prevents “frozen” bits Router collet design helps decrease the number of lost bits Specifications: Material: Steel Color Family: Black Collet Nut Threads: 20 TPI Compatible Routers: 7518, 7529, 690 and 890 series of Porter-Cable Routers What's Included: (1) Big Horn - Router Collet - 1/4" - Porter Cable Style