In addition to being a very cost-effective solution, it can handle very extreme external conditions such as dirt, dust, water, or other liquid or solid contamination. The cylinder and valves used in this system are designed to withstand these elements. The control card is the only part of the system that must be in an enclosure, but it doesn't necessarily need to be located at the cylinder; it can be several feet away and still function as well.
— Bob Atchison
ExtremeSolution