These flies are simply small clousers (about a size 6) that have a zonker strip tied in as an overwing instead of the usual bucktail. Everything else is the same as a standard clouser recipe.
Since the hook rides point up, the overwing of rabbit goes through the water as the belly of these flies. The zonker strip and the use of light (1/36 oz) dumbell eyes gives them a near nuetral bouyancy. Once wet, they drop very slowly in the water column and have a darting action that is comparable to a sluggo when stripped. I have not experimented with darker or more natural colors yet, but I believe that they would also work in the right conditions.