Universal Size: This sink is a universal stainless steel product with a spring core, suitable for various types of sink drains. The inner diameter of the strainer is 33 mm. Suitable for drain holes with an inner diameter of 34-38 mm. Easy to Install: No tools are required, it can be easily installed with just your hands. Simply remove the old bounce core and install a new bounce core. Anyone can install the pop-up drain due to 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 rebound resistance, 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 bathtubs, bathrooms, and kitchen sinks, etc. Two-Position Switch: The pop-up design of this drain strainer changes the inconvenient way of draining. It is a 2-in-1 bathtub stopper and filter. Just gently press down the top cover to switch between the 2 modes, including water retention and water drainage.