VEVOR 4-Jaw Lathe Chuck, 3 Inch (80 mm), 4-Jaw Independent Chuck, 0.1-3.15 in (5-80 mm) Clamping Range with T-key Fixing Screws Reversible Jaws, HT300 Material, Internal External for Wood Metal Lathe

Hello! Thank you for your inquiry. This 3-inch (80 mm) 4-jaw lathe chuck does not include a backing plate. It is designed as a standalone chuck, so you will need to fabricate or source an adapter plate that matches the specific spindle thread or taper of your lathe to mount it properly.