[Size and applicability] The ground expense has two colors that can be selected, including backflowing preventive (silver plating and copper, but regardless of the color, the outer diameter of the (4.2 cm / 1.65 inch of ground expense is 4.2 cm / 1.65 inches, the height of 3 cm / 1.18 inches and the width of the lower expense is 2 cm / 0.78 and 4 cm / 1.57 inch. The preventive stopper adopts the gravity evacuation switch, ie during the release, the lower cover automatically opens with water flow and closes automatically when it is not evacuated. It creates a clean and extraordinary habitat by effectively blocking the entrance of fragrance, sewage, cockroaches, mice, etc., which effectively prevents the entrance of the three -layer sealing ring. Run] Shower expense pipe stopping is easy to install and requires only a few steps: open the ground expense cover. 2. Insert the evacuation plug. 3. Close the expense cover without any additional tool assistance or tiles cutting ..[ Selected material] Floor expense Back Flow Preventive Tapa, with good corrosion and rust resistance, smooth surface and easy to clean, durable, various ground expenses, bathrooms, swimming pools, balconies, garages, basements and toilets.