Compatible with WISA cisterns from July 1987 and later, and compatible with DAL flush systems. Designed to prevent water leakage in toilet flush mechanisms. Gasket dimensions are 65mm outer diameter, 28.5mm inner diameter, and 3mm thickness. Made from durable rubber to ensure effective sealing and long-term use. Product include a total of 4pcs cistern seal, which can completely meet your daily use needs and replacement., Manufacturer: Be In Your Mind