Includes two faucet aerator keys compatible with four thread sizes: M20, M22, M24, M28. Easily switch between sizes to fit most faucets for a versatile and hassle-free replacement. This tool installs an aerator that creates a bubble flow while reducing water usage by up to 40%. It also helps maintain a steady flow and offers an adjustable flow rate, with a benefit of enhanced filtration. Made of high quality plastic for scratch-free aerator replacement. Maintenance tip: replace the aerator at least every six months to prevent bacterial buildup and limescale and to optimize flow. Widely compatible for all household faucets, including bathroom, kitchen, toilet taps and outdoor sinks. Practical and user-friendly, it makes replacing aerators straightforward and keeps daily tasks flowing smoothly. Use scenarios: - In the kitchen, swap in a bubble aerator to reduce water use during dishwashing while keeping a steady spray. - In the bathroom, adjust to a gentle, consistent flow for sink tasks or quick fill-ups. - At an outdoor sink, quickly replace to maintain efficient flow and water savings.