Functions: (1) Insect prevention (2) Anti odor, deodorant (3) Anti defection Features: (1) Easy to install, plug and play. (2) Fast drainage. (3) Adjustable Size. (4) Automatic opening when draining, closing after draining. Working Principle (1)When the water into the ground drain, the gravity of the water will open the bottom of the ABS gasket, dripping unimpeded. (2) After disruption of water, ASB gasket is automatically closed due to gravity.Completely sealed so that the gas in the pipeline, pests and over flow can not be up. Materical : ABS Metal Applications : for 3.3~4.5 cm holes Specifications: Easy to install, plug and play. Fast drainage. Adjustable Size. Automatic opening when draining, closing after draining. Package Included: 1* floor drain core 1* fixed reduction ring Notes: 1. Measurement of the item lying on the table may cause slight difference. 2. The real color of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness when photo taking. Thank you for your understanding Note: 1. Please allow 1-3 mm error due to manual measurement and 1-3g weight error make sure you don't mind before ordering. 2. Due to the lighting of the photos and the difference of monitors, the pictures may not reflect the actual color of the real item. Please make sure you don't mind before ordering, thank you! About Shipping: 1.please pay attention to your delivery address such as: name, street, house number, doorbell/email without name, etc. is correct, or the order will not be delivered correctly. 2.All items will be shipped within 3 business days after the payment is received. Most times you will receive them within 8-12 days then. The specific delivery time is depend on circumstances. 3.During the shopping process, if you have any questions, please feel free to consult us, we will reply you within 24 hours Hope you have a pleasant shopping experience!