Attached to the bottom of a Kreg hold-down clamp (sold separately), these plates and posts let you quickly position the clamp anywhere you can drill a hole. The bolt supplied with the clamp is used to attach it to the mounting plate. The steel posts, available in 2 1/2", 5" and 10" lengths, insert into any 3/4" diameter hole, and have barb-like ridges along their length to prevent upward movement when clamping force is applied.