Fox Body Lock Pin and Spring, Silver Plated
It's so easy for this little lock to disassemble and get lost, especially in the hands of fidgety students. This is a Fox OEM replacement, just the lock pin and spring (not the part that mounts onto the body) since that's the part that tends to get lost.
Pro tip: This item is in three pieces and must be disassembled for installation. When reinstalling the threaded lower section, use a bit of Threadlocker (we like the Permatex Blue brand) and it won't disassemble and get lost again!