Stuck sewer caps

[d1h]

The sewer caps on my TT are stuck and will not budge when I try to twist them off. Didn't want to break anything and ran across this gadget. Anybody used one or have another trick I can try?

[MNtundraRet]

Have you tried using a little penetrating oil on the cap tread? Sometimes forcing the cap to turn can cause the drain extension to twist loose.

[enblethen]

No offense to the one you found. It works for caps, however the open style like this works for when ...

https://www.amazon.com/Stink-Slink-Universal-Wrench-SSSW/dp/B09WZKSZ81/ref=sr_1_8?adgrpid=1343604686... 

[Cybergrunt]

A large strap wrench works. If you don't have one, you can fake it with an old belt and a pair if vice grips (old farmer trick).