The Lewis K710 Locking Safety Knife is a fixed-blade safety utility knife featuring a patented locking safety hood that covers the blade instantly and automatically when contact is lost with the cutting surface. Other features include easy blade changing with no tools required, definitive depth settings of 1/4-in. and 3/4-in. blade exposure and an ergonomic handle.Seal-O-Matic Corp.,, (800) 631-2072