Review on 🛠️ Starrett KA19 N OOPS Arbor Enlargement Tool by Jason Franco

Starrett KA19 expanding mandrel 1/4” shank flattened like most hole saws. It is 1-11/16" long so it sinks deep into the hole saw arbor. The holding end of the hole saw is threaded for standard large (5/8") and small (1/2") hole saws, just like regular mandrels. It can be held using a large mandrel and a small or large hole saw as a hole guide, and it replaces the 1/4" center drill bit. To clarify another point, this doesn't offset the center from the first hole drilled, it only does enlarged the existing hole.