RS PRO Counterbore M3, 71 mm x 6mm Cut Diameter, 1 Piece

HSS Individual Counterbores

Counterbores for cutting holes where a capscrew or fastener is required to sit flush or even below the level of the workpiece. Thread size is the size of the screw thread to sit within the hole and cutting diameter shows the size that will be cut for both the capscrew and head.