This print replaces the clasp/latch from bento box style lunch kits by Presidents Choice sold since at least 2025 if not earlier. They have been known to snap (or, at least I have one that snapped), so, rather than buying a whole new lunch kit, you can just replace the clasp.

I've printed it in PETG and it works well (and I believe PETG should enable it to survive in the top rack of a dishwasher, but your mileage may vary).