I use an oil tray covered with a screen. Both are plastic from dadant. It seems to keep the SHB in check. The hive with the oil trap has qualitatively fewer beetles than the other hives that have no oil trap. I just started using it about two months ago, they are not gone yet, but I hope to get rid of the beetle completely.
Someone also told me that the telescoping cover is a great place for the beetles to hide, so maybe a plain, flat cover might be better, but down here in rainy, humid Miami we keep with the telescope.