These are Stanley FatMax Mandrels (or Arbors) with a pilot drill bit. Designed to hold and drive bi-metal hole saws ranging from 14mm to 30mm in diameter Stanley FatMax STA81092 Hole Saw Mandrel / Arbor with Pilot Drill Bit (14-30mm) Condition: New & Sealed Key Features: Compatibility: Fits Bi-Metal hole saws from 14mm to 30mm. Hex Shank: Features a hex-shaped base to prevent slipping in standard drill chucks. HSS Pilot Drill: Includes a replaceable high-speed steel (HSS) pilot bit (replacement part: STA81102-XJ). Versatility: Suitable for use in both wood and metal
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