The jig requires a router fitted with a 30mm guide bushand 12mm diameter long-reach cutter; suitable for most common sash mortice and dead locks, with up to 3" deep mortices and a 7/8" or 1" face-plate. Deeper mortices can be achieved with a suitable size of auger bit. Also fits face-plate on a 1" mortice latch; fast clean and accurate results, even in hardwood and doors with knots; use on doors 34mm to 58mm thick.