These Faithfull Holesaw Pilot Drills are manufactured from high-speed steel for durability. They are suitable for use with Faithfull HSS arbors and most other holesaw arbors requiring the use of a 6.5mm pilot drill. Fits the following Faithfull arbors FAI HSA1630 16-30mm. FAI HSA32150 32-150mm. FAI HSA32150QR 32-150mm FAI HSA1630S 16-30mm. FAI HSA32150S 32-150mm Length 75mm. Pack Quantity 2