Inline Check Vlv, White, 3/8"

A 3/8" inline check valve in a white housing that permits flow in one direction only. Check valves like this prevent backflow, protecting pumps, feeders, and membranes from reverse pressure and cross-contamination. The compact inline body drops into 3/8-inch tubing runs found throughout reverse osmosis and small treatment plumbing.

• Connection size: 3/8"
• Inline check-valve design allows forward flow, blocks reverse flow
• White plastic body for light-duty water service
• Commonly used on RO systems, chemical feed lines, and drinking-water setups
• Internal spring or duckbill mechanism seats against backpressure
• Lightweight fitting at roughly 2 lb shipping weight

Install this valve on the outlet of a pump or the feed line of an RO unit where backflow protection matters, orienting the arrow with the intended flow direction. Confirm your tubing is 3/8-inch and that the fitting style matches your connections before installing inline.

One-Way Protection for Your Lines

This White Inline Check Valve allows water or solution to move in one direction only and blocks it from flowing back the other way. Sized for 3/8-inch tubing, it is a small part that plays an outsized role in protecting a water treatment system. Placed in a feed line, drain line, or injection point, it keeps treated water, chemical solution, or drain water from siphoning back into a place it does not belong, which safeguards both the equipment upstream and the quality of the water your household drinks.

Common Uses and Symptoms

Check valves show up wherever backflow would cause trouble: on the discharge of a chemical feed pump so solution cannot drain back into the tank, on an injection line so water cannot push into the pump, and at various points on softeners and filters. If you have noticed a feed pump losing its prime, solution mysteriously draining out of a line, or drain water backing up where it should not, a failed or missing check valve is a frequent cause. Swapping in a fresh one is a quick, inexpensive fix for an annoying problem.

Get the Right One

Because tubing size and connection style have to match your lines, confirming fit is worth a moment before you order. Tell us where in the system this valve will go and what tubing you are running, and we will make sure it is correct. We include any documentation we have, and the Water Softener Plus team is glad to help you place the valve in the right spot and the right orientation so it does its one-way job reliably.