Side-shaves and other alternative lifestyle haircuts have been usurped by straight women, muddling one of our clearest indicators with their fancy purses and dresses, straight women are unlikely to ever adopt the belt loop key ring en masse.
Short nails are one well-known way to spot a lesbian in the wild, but not everyone has sex the same way, and apparently there’s some high-femme workaround with cotton balls and latex gloves? Carabiners, which range from the utilitarian to the adorned, know no gender. A key ring also makes a perfect visual signifier for a culture that contains a full spectrum of gender presentations.