The Ambiente 3/4″ Fibre Washer is a replacement flat sealing washer measuring 24mm outside diameter, 14mm inside diameter and 2mm thick. It is intended for compatible 3/4″ UFH manifold or pumpset connections that use this exact washer size. Check the original fitting and sealing arrangement before ordering. Some current 3/4″ components use integral rubber seals or other connection methods, so nominal thread size alone does not confirm that a separate fibre washer is required.