This is to open those caps that go on 5 gallon HDPE jugs like this.

https://www.thecarycompany.com/round-plastic-tight-head-container-57wthn?utm_source=google_shopping&gclid=Cj0KCQjw-r71BRDuARIsAB7i_QPaBLsWOM7eiraZkKx4j4Kl8Avf1mR0-fwQLMVhQWDWoLIL0aHJKaAaAnGfEALw_wcB

At my workplace we work with sticky stuff opening and closing these containers routinely. After a while it gets really hard to open by hand so we have to hit it with a wrench to loosen it or use channel locks. One of my coworkers said, "If only someone could 3D print a tool to open these easier....". Well here it is.