Question about Oehlbach Banana B3

I have had Onkyo receivers in the past, and most receivers are the same: if you look at the photo of the back you'll see the big round red and black connectors. This is how they look from the side: https://www.ebay.com/itm...

Those are dual in nature: they can be screwed in to clamp on naked wires or you can use the big hole in the middle to insert banana connectors. In short, yes, you can use them with the TX8250. To buy them just goggle for banana connectors and choose a supplier that is near and convenient to you. They don't have to be fancy or superexpensive. All audio-video shops probably have them in store.

I have no idea.
My suggestion: Ask Onkyo if the size works, like the "banana plugs" that were widely used in the past.
If so, the "Banana B3" should also work.