Yeah that's what the sheath is for. I just looked up the number on mine. It's a 50s era 11-digit FSN without the 5120 prefix. EDIT: Actually, I'm more inclined toward it being a 1940's era tool with a service (in this case, USAAF) stock number. These were embedded into later 1953+ FSN's, by adding the 5120 (hand tools) prefix and other placeholders thusly: 5120-795-0895, 5120-00-795-0895.