Our popular entrance reducers with the unique sliding design makes the entrance reducer universal, fitting both 8 frame and 10 frame bee hives One entrance reducer is enough to reduce the entrance and still provide ventilation or act as a mouse guard on a bee hive. Stainless steel provides protection from corrosion or rust, ensuring your entrance reducers last year after year. 3/8 inch holes across the reducer are large enough to let bees through easily but small enough to keep a mouse from entering the hive. Can be attached to the bottom board with a basic small nail or screw or simply held in place by 2 small weights.[tab]Weight .25 lbs