On offer are a set of three drills to produce valve tube socket holes in DIY valve amp or similar projects .
They are High Speed Steel inserted tooth cutters with 5.0 mm pilot drill . Sizes are :- 16 mm ( 5/8" ) , 22 mm ( 7/8" ) and 26 mm ( 1.020" ) .
Must be used in a LOW speed drill press with nominal 10 mm chuck , essential to use a chipboard back up to metal sheet , essential to use light oil for lube & coolant . Best result is to cut half way through then turn sheet over , reduces break through burr .
No awards for trying to use them in a hand drill .
Shipping within Australia in padded bag Regd.Post $6.90