Specifically manufactured for the kitchen furniture trade for recessing circular hinges. Type 421 has two wings, no scribers and centre point while the T421 also has two wings no scribers and no centre point and is best suited for thinner laminate covered boards.

These machine bits are typically used by kitchen furniture manufacturers for recessing circular hinges. This hinge sinker is best suited for thinner laminate covered boards.
Use with pillar drills only.