This RO Membrane Housing is used to hold 12 inch reverse osmosis membranes. Both the ribbed cap and housing are one-piece injection moulded parts and when screwed together are sealed with an O-Ring.
The O-Ring is the only wearable part and if kept lubricated will last years without any problems. Over time the O-rings can go bad resulting in slight variations in dimensions and placement of the O-rings. We suggest purchasing an entire new housing if it is several years old and leaking.