Where to use it ? Applications include RO system, beverage dispensing, refrigerator ice maker, coffee machine etc.Float valves are simple to install and can save a lot of water from ending up on the floor.They can be installed in containers as small 1 gallon pails, sumps, and 200 plus gallon commercial storage containers to shut off the flow of water.Even if you do not have a large storage container a simple 5 gallon bucket with a float valve installed in it will help save money from having water end up on the floor or best case scenario just going down the drain.Also you can convert any coffee or espresso machine to automatic refill How to use it ? Installation is as easy as drilling a small hole in the container, sliding the float in and attaching using the included nut. and then pop in your 1/4" tubing into 90 degree 1/4 tube fitting , pushing until it won't go in. To remove, just push in the outer circle on either end and pull right out. You need to make sure the tubing is cut squared to insure no leaks.