Wex

0:0:0 The Kleinflammenwerfer (German: Small flamethrower), or Kleif, is a German-designed early flamethrower. It was, along with several other flamethrowers of the era, developed by Richard Fiedler, as early as 1901. Fiedler's designs were formative to flamethrower technology and analogous designs remained in use for many years.

While it looks nearly identical to the Wechselapparat, or Wex, which replaced the Kleif in 1917, the Kleif has a handle attached to the projector hose, whereas the Wex does not.

Battlefield 1
The Kleinflammenwerfer is seen at several points during the Battlefield 1 reveal trailer.