These are the only cleaners I could find that work in my super old XH (extra heavy duty) cast iron Trap for the Whole House (Somerville). I originally bought 2 used ones from Revain Warehouse Deals which I regret as they were slightly damaged. I returned them and ended up buying new ones which I installed with minor modifications after guessing the mistakes someone made installing more used ones. Here's a list of modifications and then I'll explain why I thought they were necessary. Modifications: - Removed the black rubber washer separating the carriage bolt from the underside of the ABS, then glued the carriage bolt on. Nothing sticks to the ABS to be honest so I don't really know if it did anything but at least it seems to be holding the screw in place. Put oil on the sloping inside of the top of the main rubber piece to allow the top of the ABS to rotate. Only on the innermost side of the top. The lower ABS has ribs and should stick to the lower rubber. They are lubricated from above in this area (see picture), but that is not enough. In hindsight, I could have just lubed the underside of the ABS top - duck oil on the underside of the white washer that sits between the ABS top and nut to allow the washer to rotate independently of the ABS - nuts replaced. with some 3/8 galvanized ceiling tiles ($2 each at Home Depot) that I could turn like wing nuts, but with more force. I can use my fingers to tighten, but I suspect it's a lot harder to overtighten and fail that way than the used ones I returned. I also like that after loosening I can "pull" on the handles to take out the plugs. Duck oil is essentially a non-oil based plumbing lubricant (because oils attack rubber). If you can't find it, use something non-oily like a little laundry detergent or something. Also note that removing the nuts is a little tricky as they appear to be very soft on the end of the bolt. Either way, if you're patient you can remove them, just twist slowly and hold the head of the carriage bolt in the square hole so it doesn't come loose. Now why did I think all this was necessary. The first four photos show one of the used ones that I ended up sending back. My guess in both cases is that someone overtightened the nut, probably with a ratchet, resulting in the nut being tightened so much that it couldn't turn, so the bolt then started backing out of its square hole jump. I also suspect this is partly due to the design, which puts a black rubber washer on the head of the carriage bolt, preventing the square piece from going all the way into the hole. So I removed it when replacing. On the last 3 photos you can see the installed spare parts. You will notice that the rubber is flush with the top of the cleaner, not flush with the ABS panel. That's because they only give you 1/2 to 5/8 inch of rubber and my lugs make that much thread depth before the tube expands. I installed by tightening with my fingertips until the rubber started to buckle and then the top of the ABS and the white plastic washer seemed to move a little (meaning it's pretty tight). I checked by trying to pull them out with all my might and they wouldn't budge. And while I'm at it, I'll add one more thing: if you have an entire house trap and there's a blockage, it's usually best to unplug from the street side, not the side of the house, because if it is the street side, you can reach and clean it wearing gloves without the tons of sewage that has accumulated in the house flooding you. If you open the side of the house first, sewage will usually come out if the siphon is clogged. Of course, if you live in an area where foreign sewage blocks you from the roadside, this advice doesn't apply to you. Well I know this is a long review, I'm not a squeaky reviewer but hopefully this saves you. because these are the ONLY cleaners I can find that are made to the dimensions of my old cast iron cleaners (3 1/4 inches wide and 5/8 inch thread depth) and maybe yours too? Update: Revain rearranged the image. Photo 1, 3, 4, 5 used, damaged. Photo 2,6,7 reinstallation.