Required tool: a 19 and a 23 ner strength wrench. A few rags and a bucket. This is the cold water valve with device connection 3/4 inch. Since the T-piece comes off. First Turn me I open the cold water to see flowing water no longer the top valve to then. I imagine a bucket out because it is possible that comes out of the hose water. With the 19 ner end wrench I solve the union nut of the hose. The rest I do by hand because it is quicker. Fortunately, I got the bucket standing there, as you hear, water comes out of the hose. Now I screw the John Guest tee, "Hand-tight" at the angle valve, only you can see it by the factory this is in the "open" position, then I pull down the nut with the 23 hydrochloric mouth bowl. Sometimes it squeak, so a bit. It is always important to seal the hose to check. A new looks can have different colors, there are different materials. So, this mother, I prefer now "hard hand" and then I pull them down with the 19 and 23 ner strength. The hose is tightened still rotate. Now I close the valve on the tee. Now I can connect as a filter, an osmosis system or undercounter ionizer. Then I turn the cold water on again and test whether the water is running. Down here I open the tee, again check the tightness, take the bucket away, get clean and go!