Features: Brand new and high quality Large displacement design for insect, pest, rodent prevention, and odor control Magnetic suspension deodorization helps seal the cover tightly, effectively preventing odors and overflow to support a healthy home environment High drainage capacity, effectively prevents sewer backflow and enables faster flushing Reducer ring allows flexible replacement without concern for size compatibility Compatible with floor drains in bathrooms, basements, and laundry rooms Plug and play design for simple and convenient installation; no need to replace existing floor drain Silicone ring offers good toughness, resists aging, and maintains long-term elastic sealing performance Stainless steel reducing ring is durable, corrosion-resistant, and helps prevent deformation Product Size and Usage Method (as shown in images): - Diameter: 35-37mm – use product directly - Diameter: 37-44mm – add silicone ring - Diameter: 44-52mm – use reducing ring Specification: Material: Plastic + Metal Color: Blue + Red Size: Approx. 5.3 x 4.2cm (2.09 x 1.65in) Quantity: 1 set Note: 1cm = 10mm = 0.39 inch No retail packaging included Allow 1-3cm error due to manual measurement; please confirm you are comfortable with this before purchasing Due to differences in monitor displays, the actual color may vary slightly from the image Package Includes: 1 x Drain Backflow Preventer 1 x Silicone Seal Ring 1 x Reducing Ring (Other accessories shown in image are not included)