ITEM NAME:3x Top Hex Countersink Boring Set for Wood Metal Quick Change Drill Bit Tools LJ 3x Top Hex Countersink Boring Set for Wood Metal Quick Change Drill Bit Tools LJ #aucsearchbutton #aucsearchbutton:hover { cursor: pointer;.Set Features all Commonly used Sizes Including 12mm, 16mm & 19mm all with 1/4" Hex Quick Change Shanks to Facilitate Fast Changing with a 1/4" Quick Chuck System. Countersink Sizes:12mm, 16mm & 19mm.