For removing bees from a large opening (tree). I use a piece of plywood slightly wider than the base of the screen cone that I am using and a little longer than the length of the tree opening. I mount this over the opening and then use a truck tire tube cut to size to cover the openings on either side of the plywood. I have never had any luck using the plastic tubing as the bees kept finding the way back in after a couple of weeks, even with the small 3/8" tubing. Ralph Harrison Western CT Beekeepers Asociation