Locking pegboard hook adaptor designed from scratch for my pegboard and hooks. pegboard is metal, so has very little thickness, with large 6mm holes 25mm apart. The hooks are about 2.7mm diameter

Printing individually went badly, probably because there wasn't enough time for the part to cool Printing ten at once went much better

Printing orientation is horizontal so that the plastic is strong enough to flex through the hole. once through the hole, stress is relieved, and part should last a long time.