This carbide-tipped hole saw from Diablo is tough enough to cut through wood and metal, and delivers 20 times longer cutting life and faster performance. The mandrel fits all Diablo hole saws, from 5/8 inch up to 6 inches; and it has a 2-3/8 inch cutting depth, so it can bore up to 40% deeper holes in one pass. Also, I like that it has tool-free plug ejection, so I don’t have to worry about the waste getting stuck in the center.
It is available at The Home Depot.