Set: 2 Faucet cartridges (blue and red), with 2 screws (4 mm). Can be used for single or double faucets. Ideal for bathrooms, kitchens. Materials: Made of brass and ceramic, sturdy and durable. Works perfectly, no more dripping faucets, can be used for a long time. Universal: There are 20 gears on the top of the spool, with an outer diameter of 7.5mm, an inner diameter of 4mm, and an overall length of 51mm. This is the most common size of a faucet valve. Easy to use: the red faucet valve is turned clockwise to open the faucet, counterclockwise to close , and the blue cartridge is opposed to the red. Application: Suitable for cold and hot water, G 1/2 BSP thread. Suitable for most double handles, suitable for basin faucets in bathrooms, kitchens, etc. Note: The data is all measured manually, please allow 1-3cm error, due to the difference in light and display, there will be a certain color difference, the actual object received shall prevail.