These locking pin backs are indispensable to pin collectors! Never lose another pin!
How they work:
Use the little allen key to remove the black bolt. Push the backing onto the pin, and reattach the bolt by screwing it in with the allen key until it stops turning - do not over-tighten though, or you'll bend your pin!
Each pack includes 12 pin-locks and an allen key.
Locking Pin Backs, set of 12 listed in:
, pins and brooches