Use with up to 1/2-in. threaded rod (obtain locally). Only one rod needed to suspend tray. Snap-on attachment holds QUICK TRAY PRO cable tray secure without nuts and bolts. For use with 4- to 24-in. (102- to 610-mm) tray widths. Can be used for multiple-level installations; 1/2-in. threaded rod recommended. Corrosion resistant plated finish. 7.50 x 4.00 x 1.00 in.