Looks like one of the many makers who made steel rings for single and double chainsets with the old 116mm BCD. Since it's not marked, it may have come on a lower end Raleigh with a cottered Nervar chainset. I have a few pairs of them and waffle back and forth about using them or adding them to the recycling. Perfectly good rings that will last a long time, but kind of a niche market.

Phil