Universal Size: This sink is a universal stainless steel product with spring core, can be used for various types of washbasin drains. The inner diameter of the strainer is 33mm. Suitable for drain holes with an inner diameter of 34-38mm. Easy to Install: No tools are required, it can be easily installed with just your hands. Just remove the old spring core and install a new spring core. Anyone can install the pop-up drain because of its simple structure. If you want to use it for a larger diameter, you can use the rubber ring we provide to increase the inner diameter of the sink stopper. Premium Material: The drain plugs are mainly made of high-quality and thickened copper - durable, rust-proof, crack-proof. With its good bounce and bounce resistance, the water drains quickly and closes quickly. Built-in Strainer: The sink stopper has an anti-blocking basket inside, which can collect hair and prevent back-up, providing effective filtration unlike push-button drains. Suitable for bathtub, bathroom and sink, etc. Two-position switch: The pop-up design of this drain strainer changes the inconvenient way of draining. It is 2 in 1 bathtub stopper and filter. Just gently press down the top cover to switch between the 2 modes, including water holding and water draining.