RotoRooter came out to tend to some of the roots in our line, after they left I saw water pouring out of the 3 inch cast iron cleaning hole. I bought a new PVC cap and spent 20 minutes on the wire. using a brush on my drill bit trying to clean the threads into a usable condition. The new cap didn't work, didn't poke it in any further than the old one before cutting the threads and popping out. that they weren't at the local hardware store because when you need it you don't want to wait.