It looks like a wrench to use on the sewer hose where it connects to your vehicle. I bought one but tossed it because it did not work.
https://www.walmart.com/ip/Camco-39758-RhinoFlex-Sewer-Hose-Wrench-Set/54803768?wmlspartner=wlpa&selectedSellerId=0&adid=22222222227049989840&wmlspartner=wmtlabs&wl0=&wl1=g&wl2=c&wl3=142397195898&wl4=pla-259552645882&wl5=1024543&wl6=&wl7=&wl8=&wl9=pla&wl10=8175035&wl11=online&wl12=54803768&wl13=&veh=sem&gclid=CjwKCAiAyMHhBRBIEiwAkGN6fFae-JlwFO2R-MUKde9i6ctm6RKvulbeI7isjXsWglrQ4awB0Ig74BoCpaAQAvD_BwE