I had a rec. swarm catcher years ago, that had 2 small like 1/4" pieces of wood that would set in a molded out area at both ends of the trap to rest frames on. that trap was made out of same material the round ones are, only was easier to take out swarms as they were already on frames. I checked all the bee supply places and cannot find these does anyone know where they may be sold at ? Even though the round ones work, i don't really like them.