What Size Toilet Flange for 3 1/2″ ABS Pipe?

I'm trying to purchase the correct toilet flange but having difficulty.

The bathroom was roughed in years ago in ABS and we are trying to finish it out. As a I measure the toilet waste pipe, it measures 3 1/2" inches from outside edge to outside edge. The inner diameter (inner edge to inner edge) is more like 3 1/8"+. So, we are close to 3", but it is still slightly wider than 3".

The last flange I purchased advertised itself as "able to fit INTO a 3" ABS waste pipe", however it was in actuality the exact same diameter, so it did not insert into the pipe… it just sat on top and was of course no help.

Before I make yet another trip back to the store, I wasn't sure if there was any wisdom out there on the best product to go with given my situation and pipe measurements. Or perhaps I'm not understanding the terminology

Thanks.