[Premium Material] The faucet aerator is made of ABS plastic, which is easy to install and durable. Plastic vents are more durable than metal grille vents because they won't rust. [Splash Resistant] By mixing the water flow with air, it creates a lot of air bubbles, which makes the water flow smoother and less splashing. The filter inside removes most impurities. The water is cleaner. [Water saving] By adding air, the water flow is stable and strong, which increases the flushing power and effectively reduces water consumption. This allows you to save up to 30% water. [Standard Size] You will receive 10 green aerator inserts with 21mm upper outer diameter and 18mm lower outer diameter, with 10 23mm rubber washers (green) and 10 21mm rubber washers (grey) ). [Wide scope of application]Suitable for all places where water saving and filtration is needed, repairing faucets with low water flow or damaged aerators, no need to replace the faucet. The size is manually measured, please allow the error (1-3cm). Due to different monitor pixels, there may be color difference, please refer to the actual product. After receiving the package, if there is any dissatisfaction, please contact me first, do not leave negative feedback easily, thank you and have a nice day.