Kreg KJD/DECKBIT Deck Jig Bit Depth Collar Allen WrenchSpecialized single piece stepped drill bit was designed exclusively for drilling concealed holes with the Kreg Deck Jig. The bit creates an unobtrusive hole on the edge of your Deck Boards. The bit comes complete with a rugged Depth Collar which controls the depth of your drill bit when drilling. The Depth Collar is secured in place on the bit with the included Allen Wrench. This Deck Jig drill bit and the KTX driver bit which came with your Deck Jig,