Do you have an outside faucet that needs a new key? Have you purchased one online, only to find that it is a loose fit (such as a Bonfix key)? This key may be what you're looking for. The inside square space is slightly tighter than the keys you'll find online and may fit perfectly.

I printed the faucet with PETG as it is to survive in often wet conditions outside. The result seems easily strong enough but time will tell.