These microfiber refills are Eco-friendly and can be washed up to 500 times. These refills are superior to the disposable version because they are machine washable, 100% eco-friendly microfiber, reusable up to 500 times, 70/30 blend of Polyester/Polymide, microfiber won't scratch any surface, removes germs and bacteria that cotton can't. Microfiber is better than cotton at cleaning and sanitizing. It has more surface area than cotton allowing it to be more absorbent. Its fibers are finer/thinner allowing microfiber to capture bacteria that are too small for cotton to grab. Microfiber studies show mopping with microfiber reduces bacteria and germs by 99% whereas cotton only reduces bacteria and germs by 30%. Microfiber is easier to use and much more effective. Most hospitals & schools prefer microfiber over cotton. Cotton takes 3 times longer to dry than microfiber so either hang microfiber to dry or use a clothing dryer on LOW heat for 1/3 the time you would set it to dry cotton. Save on gas or electric when you switch to microfiber over cotton.