Portion your shampoo or conditioner with a pump cap. This will eliminate waste and make your product last longer. Works on standard size litter bottles like redken, Aveda, matrix, sexy hair, Bossley, wella, enjoy etc. (Does not fit on tall lanza, joico, thermafuse, Schwarzkopf or other very tall litters). (Does not fit wide mouth bottles or very small neck bottles like iso, keune).