We have a large range of Weldon shank arbors to fit into our machines.All machines are supplied with the standard arbor for that particular machine but there may be a need for a replacement or a longer depth of cut or conversion to coolant, etc.Arbors are either 1/2" x 20 UN fitting, MT2, MT3 fitting Weldon shank sizes 3/4" and 1.1/4" are available (cutters up to 2.1/4" are 3/4" shank - cutters above 2.1/4" are 1.1/4" shank).An MT3 to 3/4" Weldon Shank to Quick Release arbor is now available.