The chamfer cutter can be used with or without a ball bearing. It can be used for both plastic and solid wood edges. Always a sharp router due to the reversible blade system|The cutter is supplied with a sturdy steel ball bearing. Reversible blades for 45° chamfer cutter for edge trimming, with ball bearing. optimised bearing mount suitable for 12.7 mm ball bearing guide or no ball bearing guide|12 x 12 mm reversible blade can be used 4 times. for OF 1010, OF 1010 R, OFK 700, MFK 700, MFKC 700