Odal,,,salesmens sample board.. These are probably the hardest to find.. I've always heard there was a ring but haven't seen one in hand..

Here's another set from my files,,plain but matched sets are becomeing harder and harder to find!:

81482-6030-1-W.jpg (34.34 KB, 315 downloads)
81482-6030-2-W.jpg (44.54 KB, 316 downloads)