material penetration & less walking NBHSI660 3/8" Spring-loaded Pozi-Lock Mandrel 628204616607 NBHSI662 7/16" Spring-loaded Pozi-Lock Mandrel 628204616621Item: Hole Saw Adapter 628204616508HOLE SAW KIT | PROFESSIONALgrade, Bi-Metal hole saws cut everything from woodsteel, cast iron and stainless steelallows for easy chip removal and faster, cleanerallows for increased cutting depthbacking plate adds strength & stability and prevents3/4", 7/8", 1", 1-1/8", 1-3/8", 1-1/2", 1-3/4", 2", 2-1/8",+ 3/8" Quick Change Mandrel & 1/4" Hex Shank Mandrel