Set of 8 holesaws complete with arbor and pilot drill.  For cutting wood, plastics and laminates, 25mm cutting depth.  Cutter sizes 25,32,39,44,51,57,63 and 68mm.  Hexagon shank 8mm diameter.  Replaceable pilot drill.

To use, remove all the blades except the desired cutting diameter.  Kreator brand from Belgium.