Fittings & Tubing
John Guest - Inline Tube Check Valve Quick Connect Fitting
price
from $15.45
John Guest - LLDPE Polypropylene Tubing
price
from $0.25
John Guest - Acetal Union Elbow Quick Connect Fitting - Grey
price
from $3.43
John Guest - Polypropylene Inline Straight Ball Valve
price
from $9.16
Isopure Water · Fittings & Tubing
Quick-Connect Fittings & RO Tubing
Reliable water connections come down to good fittings and the right tubing. We carry a deep range of John Guest quick-connect acetal fittings — connectors, elbows, tees, reducing unions, ball valves and inline check valves — plus polyethylene and LLDPE tubing sized for RO and filtration plumbing.
How to choose fittings & tubing
Match tube OD to fitting. Fittings are sized to tubing outside diameter (1/4", 3/8", 1/2") — measure the OD, not the ID.
Quick-connect makes it easy. Push-to-connect acetal fittings seal without tools or tape and release cleanly for service.
Know your thread. Connectors come in NPT, BSP and UNS threads — match the thread on your housing or faucet.
Add a check valve. Inline check valves prevent back-flow into the membrane or pump — cheap insurance in any RO build.
Building or repairing a line? Tell us the tube size and we'll pull the fittings.