EPDM rubber valve balls, suitable for all diaphragm pumps. They are deal for water based, acidic & alkaline products. Suitable for an array of different air driven double diaphragm pump manufactures as well as all sorts of other non-return valve applications. The sizes listed are approximate. All balls are in stock and available for next day delivery. If the size you are looking for is not listed here, please contact us for prices & lead time.