Reverse Spotfacer, 1/4 in Pilot × 7/16 in

A back spotfacer cuts the seat on the side of the part you cannot reach face on: the pilot goes through the hole, the cutter is fitted behind it, and it cuts on the pull. Spotfacing covers squareness and depth, the spotface size chart gives the bearing diameter a head, nut or collar needs, and the drill guide gives the hole the pilot goes through. The cutter body is sold without a pilot: the pilot is a separate item.