Not sure who made these, they're black crinkle finish with big plastic knobs on the release. Bottom has 1/4 - 20 mounting hole in each ring. Felt lined - felt in really good condition and the holes where the (optional) adjustment screws go thru are tiny. These are drilled and tapped for use as a guidescope setup. I used this for short tube 80mm scope: it will work better on something a little smaller than 80mm scope since it is a little tight for wide range of adjustment.
$25 plus shipping. I have an aluminum bar (heavy doorway threshold) set to hold these onto a 10" sct ota that i'll throw in if you pick it up as it'd make shipping a whole new game over the rings alone.
thanks for looking,