Westcott 10″ 3 Jaw Lathe Chuck 2 1/2″ 6 pitch. Jaws can be adjusted independently or together. All parts move freely. 6 threads per inch on back plate and I believe it is 2 1/2 in diameter. No handle (1/2 square). The jaws can be move together using the 1/2″ square end or a 7/8″ wrench from the side.