4" 1-10 THREADED BACKPLATE FOR 4 JAW CHUCKS (3900-4142)

4" 1"~10 Threaded Backplate for a 4-Jaw Chucks Fits most plain back chucks. Must be machined for concentricity. Made of high grade casting steel. Assembly instructions included. Bolt circle is 3.3". Number of bolt holes is 4. Shipping Weight: 3 lbs