Hole Saw Arbor, Arbor Type Standard, Thread Size 5/8 In.-18, Arbor Shank Style Hex, Arbor Shank Size 1/4 in, Fits Hole Saw Dia. - Imperial 9/16 in to 1 3/16 in, Fits Hole Saw Dia. - Metric 14 to 30mm, Pilot Bit Shank Style Hex