Charlotte Pipe 3 in. x 4 in. ABS-Cast Iron Adapter Hub x Spigot ABS00123R1000HD - The Home Depot
Fernco 4 in. Service Weight Cast Iron Hub x 4 in. Sch. 40 PVC Compression Coupling P44U-405 - The Home Depot
Fernco 1056-43W Reducing 4" x 3" Flexible Pipe Coupling Socket Plumbing Plastic PVC ABS, Cast Iron, Lead in White - Walmart.com
No-hub coupling, cast iron to ABS: tricky?
ABS Toilet Flange Into Cast Iron Pipe | Terry Love Plumbing Advice & Remodel DIY & Professional Forum
Fernco 4 x 4 in. Cast Iron or Plastic Flexible Coupling - Amazon.com
Charlotte Pipe 3 in. x 4 in. ABS-Cast Iron Adapter Hub x Spigot ABS00123R1000HD - The Home Depot
3001-22 - Fernco 3001-22 - 2" x 2" ProFlex Coupling (Cast Iron, PVC, Steel to Copper)
ABS Cast Iron Adapters – Canplas Industries Ltd.
Fernco 4" Clay/Cast Iron x 2" PVC/ABS Compression Donut at Menards®
plumbing - Why did my plumber use a cast iron to plastic coupling in one location, but not in the other? - Home Improvement Stack Exchange
Somebody actually connected ABS directly to cast iron with lead and oakum. A lot more work to do it wrong than to just use a no-hub coupling. : r/Plumbing
Fernco 1056-22 2-in. Flexible PVC Pipe Coupling for Cast Iron and Plastic Plumbing Connections in Brown - Amazon.com
4" CI to 4" ABS - what is the correct flex coupling | DIY Home Improvement Forum
No-Hub Couplings Changed the World of Plumbing
cast iron to ABS? (or pvc) | DIY Home Improvement Forum