About This ✅This set of Pin Jaws is Dedicated for VINWOX 3.75" SCK4-3.75 & 4" SCR4-4 4-Jaw Self-Centering Wood Lathe Chuck, Same Jaw Fixing System Across PSI “C” Series and Craft Supplies 3.75” Apprentice Chuck – TOTAL INTERCHANGEABILITY! (Won't Fit to Nova, Record Power, Vicmark & Oneway Chucks) MAKE SURE TO CHECK YOUR LATHE CHUCK FIT FIRST to Avoid Unfitting or Return. ✅Ideal Gripping in the Expansion Mode for Vases, Cups, etc ✅Grip Inside a Hole Bored from 1” to 2-1/4” ✅1” Length Extension Provides Optimum Gripping Power with Minimal Damage to Wood Projects ✅Pin Jaw Specification: Specifications: Outer diameter 7/8"; length 1", Weight 0.70 LB (0.32 Kg), with 8 Mounting Screws Overview Brand : VINWOX Material : Metal Item Diameter : 2.25 Inches Item Weight : 0.37 Kilograms Compatible Devices : Lathe