... DIFFERENT WOOD PLUGS PRODUCTION ON HIGH EFFICIENCY High quality plug cutter for wood in different types on high working ... efficiency.Diameter for plug(metric):6,8,9,10,12,14,15,16, ... 20mmDiameter for plug(inch): 1/4", 5/16", 3/8", 7/16 ... ", 1/2", 5/8"Shank Type: 1/4" Hex Quick Change System or 8mm diameter round straight shankSurface treatment ...