The Hydronix SPV-25CAPORING 2.5" O Ring is used with 2.5" Hydronix RO Membrane vessels.
The o ring is used for Hydronix SPV-2521 and Hydronix SPV-2540, Stainless Steel Membrane Housing Vessels.
The Hydronix SPV-25CAPORING will not work with Liquatec Membrane vessel housings. If you need a replacement part for your Liquatec vessel housing you will have to purchase a new Hydronix housing.