eFS are the initials of the brand's founder, Eurico Ferreira Sucena. The company began producing bicycle accessories in 1911. The motorcycle business started much later, in the early 50s. From 1969 onwards, the brand changed dimension, exporting to all major continents.
To illustrate: an EFS GT Super motorcycle with a Sachs engine

Image credits: D.R.
To illustrate: an EFS GT Super motorcycle with a Sachs engine

Image credits: D.R.