ROCO™ Wood to Steel Screws are specifically designed for increased holding power and an incredibly clean finish. When engaging the wood, the screw effortlessly drills through the wood while the wings mill an oversize hole. When the screw engages the steel base, the oversize hole prevents the threads from engaging the wood, lifting wood and steel apart (jacking). The specially engineered drill point cuts fast through the steel base and once penetrated, the wings easily break off. The threads then tap through the steel and firmly clamp the wood and steel together.