Hole saw's size:

3/4"(19mm),7/8"(22mm),1-1/8"(29mm),1-3/8"(35mm),1-1/2"(38mm),1-3/4"(44mm),2"(51mm),

2-1/4"(57mm),2-1/2"(64mm)

Arbor :3/8 hex shank,3/8 chuck,1/2-20 UNF, 

          7/16hex shank,1/2 chuck,5/8-18UNF,

 Adapter fits arbors 1/4--7/16 shank

 Drill : 1/4" Hss pilot drill,75mm long