It sounds like some sort of variant on an excluder, and might have some parts you might not see in the catalog illustration. (My first thought was it sounded like a propolis collector,but then I read more closely and thought "Hmm, sounds like there may be features not apparent." I'd guess you use it as the first unit on the bottom board, between it and the hive body. I've never seen one of these, though. --Jane Beckman [[log in to unmask]])