WORLDWIDE SOURCING KJ-013 Flexible Pipe Coupling, 3 in, Socket, 3"

I don't know what a "socket" is. Here's what I used this product for: to connect my 3" ABS pipe to my 3" corrugated drain pipe. I have no idea why this connection size is not available at either local box store. When I tore up my clogged gutter pipe underground, I discovered that my contractor had used duct tape to make this connection (3" ABS to 3" corrugated pipe). He must have also had trouble finding this size connector. Anyway, that's how I used it and it works great.