Bahco 930 Arbor 3/8in is suitable for 14-30mm holesaws for use with hand held machines. All arbors are hardened for maximum strength. The 3834 Series Arbors are available in a range of sizes suitable for different chuck capacities. Shank size: 8.5mm.This Arbor has the following specification:Size: 14-30mmShank: 8.5mmAdditional Information:• Accessory Type: Arbor