Aristo Watch Import Company was an American technical instrument company that imported high-end watch movements during the 1940s through the 60s and sold watches under their name primarily to the medical and scientific community.  Many of their ads from the era can be found in medical journals and in science publications such as popular science.  Since Aristo marketed toward and focused on a very small market at the time, there are few watches baring their name, and even fewer executed with a Valjoux 72c.   

The Valjoux 72c is a very complicated triple calendar chronograph movement, and one of the most coveted column wheel chronograph calibers of all time.