Parylene's high altitude/vacuum performance started gaining attention within the aerospace industry in the 1970's. Parylene's inherent barrier properties were important, but even more so was the nature of its vacuum deposition process (VDP). Being deposited in a vacuum meant the Parylene trapped no air in or on a coated device or component. In high altitude/lower pressure environments, this trapped air can expand and potentially rupture the coating. The result is not only a destroyed device but also the potential for a destroyed mission as well. Parylene also has higher temperature capabilities in the absence of oxygen — the vacuum of deep space. Add the low mass of these very thin Parylene coatings, and it's clear to see why SCS Parylene is a highly prized within the aerospace industry.