Reddit reviews K2533 JJ 1/4" quick connect fittings. Granular activated carbon inline water filter for refrigerators, undersink, houshold applications.

You could do it for much cheaper with something like this http://amzn.com/B00BA9DE94, which has a 1500 gallon lifespan. You need to T-off from your existing plumbing and add a spigot/valve to dispense the water.

I am trying to connect an RO type faucet like this
to a standard sink supply line. Id like to tee off of the sink supply line to provide the faucet with its own water supply (it will have an inline filter). I am not sure of the correct reducers to get for this. I ordered this
but the male end is just a touch too large. I am obviously not the most knowledgeable when it comes to plumbing sizes, but I would greatly appreciate any help!