20as
20as is a designation that can refer to several different things, depending on the context. Without further clarification, it is difficult to provide a specific and definitive article.
In the realm of computing, "20as" might be a part of a filename, a software version number,
In industrial settings, "20as" could represent a model number for a piece of equipment, a part number
It is also possible that "20as" has meaning in a specialized field like chemistry, physics, or engineering,