15pcs bi-metal hole saw

11pcs bi-metal hole saw :
     3/4"(19mm),7/8"(22mm),1"(25mm),1-1/4"(32mm),1-3/8"(35mm),1-1/2"(38mm)
     1-3/4"(44mm),2"(51mm),2-1/4"(57mm)
     2-1/2"(64mm),3"(76mm)
2pcs arbor
1pc spring
1pc 12" extension shank