There are four common sizes available. The units match the size of Omnipure ™ sediment and pre and post-carbon filters. Many of those components are available when ordering RO modules.
TFC membranes are available in any of the standard sizes. All of the standard units come with John Guest fittings. Two options are available: built-in SS flow control orifice and/or product side check valve. Other sizes or port configurations or port types are available, but minimum order requirements apply.