Below are some advantages: Very simple in its operation! You choose 2.2 as the value, and that is that. increases with a difference of 0.5 (see example 22022) pumps up Below are some downsides: - Here's a new spin on it. It was possible to carry out in a different manner. (snap) Because it is impossible to fit the wire into the box, especially during the cold, you should simply twist it and leave it nearby.