Review on Enhance Drilling Efficiency with Koopi BI METAL Replacement Tools for Plastic Cutting by Ricardo Knight

Seems like a good buy. I was about to drill a hole in very thin sheet metal/aluminum. he was as big as a credit card. It worked, but the hex screw was removed with the hex tool provided. I sent it back to Hols for a refund. It would be nice if the hex screw was made of a harder metal.