8PCS Gear Milling Cutter HSS 8H Set 8 Pcs DP16 PA14-1/2 Bore22 No1-8 Involute Gear Cutters Diameter 55mm Set 8 Pcs Dp16 PA14-1/2 Bore22 #1-8 Involute Gear Cutters pressure angle: 20 degree Outside Dia: 55mm Inner Bore: 22mm Material: HSS