Type 1: E.g. 1 & 2: For multiboring bits (PF11M or PF07M). Fix to the bits helix to obtain countersinks on solid wood and laminates.
Type 2: E.g. 3 & 4: For multiboring bits (PF10M or PF06M). Fix to the bits shank to obtain countersinks on solid wood and laminates.
*Note: “d” is the diameter of the drill bit.