This is a connector for the sliding door damper of our bathroom door. It is a heavy glass door, and one of our kids enthusiastically smashed it shut, breaking the tiny connector between the damper rod and the door hook. I took measurements and re-modelled the connector, which works great again.
The original model seems to be a Titus damper, looking like a C connector of their product lineup (961-4048). Since it is difficult to get just these replacement parts (the door company sells the entire system as a whole), I figured it is economically more sensible to replace only the broken connector part.