Starrett A1-1 SDS Plus Arbor for use with holesaws ranging from 14-30mm.
Specifications:
Holesaw Pairing: FCH and CT.
Holesaw Diameter: 14-30mm (9/16-1.3/16in).
Arbor Shank Sizes: 8.75mm (11/32in) hex (excluding SDS-Plus Arbors).
Screw Thread: ½1/2in-20 UNF.
Chuck Size: 9.5mm (3/8in).
Drill: HSS Drill Length: 79mm (3.1/8in).