4" x 4" Donut

As advised by the manufacturer, this fit the task it was meant for! CI to PVC

I could slide the adapter onto the 4" PVC pipe, but then I could not slide the adapter into the bell end of the Cast Iron fitting. No matter how much force was applied, I couldn't marry the two pipes together. I ended up grinding off a thin layer of rubber from inside AND outside the adapter. This allowed me to force the PVC pipe into the Cast Iron. Difficult and time consuming but it worked.

House was built in the late 50's. Removed a old toilet iron closet bend from the CI pipe. The Needed a donut to fit into the XH cast iron hub. Took a digital caliper and got an ID of 5.24. Called Fernco and they told me my best bet was model A426-405, which has an OD of 5.21. Ordered from supply house Tues afternoon and to my surprise UPS dropped it off the next morning. First put the donut in the hub, then with some soapy water as an aid I hammered a 4x3 flush bushing in that. Used a piece of wood and a rubber mallet. I had to hit the wood really hard. I was worried that I was going to break the Cast Iron or maybe the donut was a size too big. Eventually it went in a quarter of an inch at a time. Haven't tested yet but I'm confident this won't leak a bit. I also believe the next size down , model 412-405, which has an OD of 4.147 would of been a easier fit but snug enough not to leak.

I needed a donut to fit my 4 inch xh cast iron pipe. (Extra Heavy). The plumbing store near me only sold the sv (service grade) cast iron donut. The sv donut may have worked but I felt more confident with this donut because it's dimensions matched the xh pipe. Called SupplyHouse and had the part the next day. Great customer service!

4"x4" neoprene gasket used to seal PVC to cast iron hub. Product fit tight just as Fernco tech rep said it would. Since this is a toilet connection I wanted that too. Even though I used detergent to smooth the install I had the best success fitting the gasket into the hub approx. 1" deep, inserted the 4" PVC as far as it would go, then took a wood block and pounded around evenly. Result was a very tight joint. I will see over time how well I did.