Features: Nitrile rubber is easily affected by acetone, ether, esters, ozone, sunlight and weathering, so the rubber O ring washer should not be applied in motors that generate ozone, welding equipment or in applications exposed to UV light. Easily repair your leaky plug with the nitrile rubber O ring, refreshing the kitchen sink and saving water effectively. The pop up basin waste gasket is in the shape of circular, universal to most bath plugs. Please confirm the size of the rubber O ring washer before purchasing it. Specifications: Material: nitrile rubber Color: black Size: Outer diameter: 38 mm/ 1.5 inches Inner diameter: 35 mm/ 1.38 inches Package includes: 30 x Replacement O rings Notes: Please allow slight deviation due to manual measurement. The colors may exist a slight difference due to different screens.