This tct two wing slotting cutter is ideal for biscuit jointing sizes the set is supplied with 3 ball bearing guides to suit the three sizes of biscuits available a slighlty longer cut than the length of the biscuit is required for ease of alignment during assembly supplied with instructions no 0 45 mm x 15 mm x 4 mm suitable for 8 12 mm boards use bearing b19a 905 mm depth no 10 53 mm x 19 mm x 4 mm suitable for 13 18 mm boards use bearing b16a 106 mm depth no 20 58 mm x 23 mm x 4 mm suit