If you arrange them properly, they form a single ring.

There was only a single ring on his right hand, and like me, he wore no watch at all.

He wore a single ring of some deep blue stone.

The third time he got a single ring, and the phone was picked up halfway through it.

This was sealed by the exchange of a single ring.

He showed how a single ring may be cut to produce two.

All the hard data they had came from the transportation of one single solitary ring.

For the next three days I had not a single ring at the bell of any sort whatever.

The phone on the other end of her call was picked up after a single ring.

So imagine that instead we just have a single ring.