Back in 1968, in one of the spare parts list for the Nagra III the rotary pilot indicator was described as a “Voyant rotatif SASSE” in French. And in the English version it was written SASS indicator. Both of these are incorrect. Actually the word in French should have been “SAS”. A SAS in French actually means “an airlock” or the space between two doors outside which the pressure is different. The term can also be used to describe the lock gates on a canal. From this idea of two doors (the rotating parts in the indicator) was kept and somebody, nearly 30 years ago decided to call this peculiar little indicator a SASS INDICATOR.