The TurnLock concept turns changing guide bushings and installing router attachments into a simple matter of a 1/4 twist - no tools needed. Align the TurnLock bushing inside the TurnLock base and twist. The cogs on the outside of the bushing slip into the slots on the inside of the base, locking the bushing in place. Base plate is made from clear resin that increases visibility of the work area and allows for more consistent alignment of router bits with any template shape. Special ride pads keep router base scratch free. TurnLock base attaches to any of the Milescraft router attachments. Set contains 7" universal TurnLock base plate that fits most routers up to 3 HP (horsepower), centering pin, top hat adaptor that converts non-TurnLock metal bushings into TurnLock Quick Change Bushings, and 8 bushings (5/16", 3/8", 7/16", 1/2", 5/8", 51/64", 7/16", 5/8" extended nose). Detailed instructions included.