The truth is that my a/c has a leak and every year I need €50-60 for a refill. I decided to try this solution this year. Attention now! Since your system has a leak and no longer blows cold, know that it will be full of air. Therefore, as soon as you connect the valve and go to add the refrigerant, the pressure gauge will immediately go all the way to the red. You need to disconnect the bottle while the hose is still on the low-pressure valve and let it empty of air (with the engine and the a/c running, of course). Once it stops blowing air, then screw the bottle on and open clockwise so the refrigerant flow starts (the bottle upside down). Always monitor the gauge and the pressure. It will not be a linear reading as many may expect. So when the needle passes into the red area, close the supply (or turn the bottle the other way) and wait to see where it stabilizes. Ideally, stop the process when the needle reaches the "40 stop" indication. My a/c works again, but I know that in reality this is a "patch" and I may even cause damage. In cases like mine, the best option is neither a refill with a special machine at a workshop nor, of course, the use of Cool5, but if the financial means are available, repairing the a/c. Otherwise, the product does what it promises, provided it is used for the job it was made for, namely topping up an a/c that has no other problem or total loss of refrigerant. For that reason I give it 5 stars, with this note however.

The car worked fine, but it is only for topping up, so you should know that; otherwise it needs a machine to empty it, etc., at a mechanic.