1、The drainage efficiency is strengthened with the influence of external drainage outlet. 2、Practical functions. Effectively keep out mosquitoes; Seal stinky smell and odor from sewage gas; Prevent the drain water from backing up to the room. 3、Sporting large outlet for fast drainage. 4、The ring and filter screen can be tailored according to the actual size of the sewer, say goodbye to sewer blockage. 5、Made from premium material, totally environmental-friendly and non-toxic, safeguard for your family health Features: The drainage efficiency is strengthened with the influence of external drainage outlet. Practical functions.  Effectively keep out mosquitoes; Seal stinky smell and odor from sewage gas; Prevent the drain water from backing up to the room. Sporting large outlet for fast drainage. The ring and filter screen can be tailored according to the actual size of the sewer, say goodbye to sewer blockage. Made from premium material, totally environmental-friendly and non-toxic, safeguard for your family health Specification: Condition: 100% Brand New Color: As shows in pictures Material: ABS+Silicone ring Diameter for filter screen: approx.12cm / 4.72in Package Included: 1* Filter Screen Notice: Please allow 1-3cm error due to manual measurement and make sure you do not mind before ordering.