Two-Piece Reversible Jaws; Each jaw is composed of top and bottom "master" jaw; Jaws can be easily reversed for extended clamping range; American Standard Tongue and Groove Style; ISO3442 Highly durable; Steel inner mechanisms are quench hardened to increase toughness D1-6 Camlock Adapter; Comes with a finished backing plate ready to mount chuck to lathe spindle 7 7/8" Body Diameter; 2 9/16" Through-Hole Diameter; For 0.16" to 7.87" Workpiece OD; For 2.56" to 7.87" Workpiece ID Includes: Lathe Chuck, Adapter Plate, Chuck Key, Mounting Bolts Lathe Chuck With Adapter Plate Combo Set