INGCO Combo Set 9-piece hole saw set .

9-piece hole saw set AKH0091
Material: HSS M3 Bi-metal
Size: 19mm(3/4″)/22mm(7/8″)29mm(1-1/8″)/38mm(1-1/2″)/44mm(1-3/4″)/57mm(2-1/4″)
1x Arbor: 3/8″ Hex Shank, Fit size: 9/16″~1-3/16″
1x Arbor: 7/16″ Hex Shank, Fit size: 1-1/4″~8-17/64″
1x Adapter Arbors with 1/2-20 threads to fit hole saws 5/8-18 threads.