Mur-lok Elbow Check Valve 1/8" Male NPT x 1/4" Push Connect
Check valves only allow water to flow one direction. 1/8" Male NPT x 1/4" Push Connect elbow check valves are typically used on the product water output of RO membrane housings to protect from back pressure and allow auto shut off valves to operate correctly.
The Check valve will go on the RO product water line. Feel free to let us know if you have any further questions!