It should be noted that to attach to the supply line the tee included has half inch connections. It is normal to have 3/8" connections at the shutoffs under the sink so it appears the 1/2" tee is intended to attach to the fixture end and not the shutoff end which may be why so many reviews mention the 3/8" connection being a problem. Disconnect the supply hose from the faucet cold 1/2" connection and thread the tee on to the faucet and then connect the supply hose to the bottom of the tee. If your faucet has the hoses built into it that cannot be removed you will need to find another way to connect the supply. Check your faucet to see if you can thread 1/2" hoses onto the bottom to be sure. I read a few reviews that mentioned leaks occurring when the filter split. That seems like a pretty huge flaw if that is possible. To be safe I didn't mount it under the sink. It is an inexpensive setup and I can see how the fittings could cause a problem especially if the hoses aren't cut properly and squarely. Also the hose is marked to indicate that you have fully pressed it in and engaged the fittings on the filter. Once you push the hose in it seems like its tight but you want to push it in a little more, about to the lines on the hoses. If using another hose or a cut portion of the hose you need to make sure it is fully engaged. The connection to the bottom of the spigot was a little odd, it seemed you could put a lot or a little of the hose in and the water fills the full length of the threaded portion under the sink. You want to make sure that the insert that goes into the hose is inside the nut when securing, you can easily feed more hose into the fitting than is necessary and you won't have the hose insert under the nut to assist with the compression seal. I did not have any leaks from the press on fittings or hoses. I did not use the tee for the supply and instead opted to use longer 1/4" hose I had purchased for an Ice maker install and ran the tubing into the basement directly below the sink and conveniently above the sump pump hole should any major blowouts occur. This is not possible in all situations but this would also allow me to tee off the filter again for use as the ice maker filter with a bypass plug for the fridge filter. Without the sink supply to attach to you would have to find another cold water supply. I had an unused washer hose connection in the same location so it seemed a waste of time to solder in a tee and shutoff or using a saddle valve (I wouldn't use a saddle valve). I purchased a screw on hose connection to 1/4" compression fitting and inserted the supply into that, a quarter turn of the hose bib was all I needed to have adequate water pressure to the filter. The filter fills a gallon jug two to three times as fast as our old faucet mounted Culligan Filter that served us well for the past three years. The water seems to taste the same but we have only had it three days. The quality of the spigot is good enough for me, it seems solid enough but I don't have anything to compare it to. If we have a problem with it then I will replace it someday, no big deal. I am happy we have filtered water and could finally replace the sink faucet we neglected to change because we were dependent on the old Culligan filter. We filter for taste and Chlorine as we have city water, it should last us the full 12 months between filter changes I hope.