What thrill of childhood does this object unlock?
Skate keys were once used to tighten and adjust old fashion metal roller skates that strapped to your shoes. Without the key the skates would be useless. The hexagonal loop turned the bolt that adjusted the length of the skate and the tubular end slid onto a pin that tighten the toe grips. Skaters wore the key on a string that they slipped through the long narrow hole in the middle which was typically worn around their necks.