Review on Milwaukee 49 56 0132 4 Inch Hardened Hole by Mario Beaklini

I have a set of these hole saws for my drill press. Unlike many hole saws, which rely on friction to secure the saw to the drill's slot, they work with a pair of holes that match the pins on the slot. Great design and this particular saw mounts the same way. These are the only hole saws I buy.