What’s the oldest things you’re wearing today?

I wear my Army Dog Tags issued in 1987 every day. To be honest I recently started wearing them after taking a fall and ending up in the hospital, the fall resulted in a head injury and the loss of blood, I was given blood in the ambulance but because my blood type was not known I was given the wrong type. I really hope that type of incident never happens again but if it does my Dog Tags have all that information on them.