Sometimes referred to as Hole Cutters, the purpose of the Holesaw (often spelt Hole Saw) is basically to cut holes into various types of material, including wood and metal.
It does this using a ring-shaped blade that cuts a round hole without needing to cut up the material inside the hole.
As a result, this creates a more efficient method of cutting a hole than typical drill bits are able to, as they do cut out all of the material.
Holesaws are used in a similar way as traditional drill bits, in that they work as an attachment to a power drill. They are capable of cutting holes as deep at the cup-shape around the saw will allow.
At Howarth Timber & Building Supplies we offer Holesaws in various sizes from 16mm up to 76mm.