John Guest Non-return Valve - 12mm Push-On Fitting lights while still being hard-wearing

while still being hard-wearing

These should not be adjusted too tight

The Four Season Evolution Hatch has four openings which can be individually controlled by the simple twist controls

Thinner inserts will need to be packed out

John Guest Non-return Valve - 12mm Push-On Fitting lights while still being hard-wearingPush on fitting to allow flow in one direction only. Join two sections of 12mm red black or blue pipe. Easy to use Push fit technology Quick disconnection, no tools needed! Working Pressures and Temperatures: 10 Bar at 20C 7 Bar at 65C intermittent hot water Minimum temperature 1C Typical crack open pressure 0. 02 Bar Push on fitting to allow flow in one direction only Not recommended for compressed air and vacuum uses.