Belgia n BEM 4 GP

The Belgian Engicom Mask, 4th generation, General Purpose (BEM 4 GP) had an adjustable inlet, allowing for three different filter positions.  This example was made by Engicom in 1991.

 

Similar masks in my collection:  Italian C60

Rubber stamp
Rubber stamp

Date stamp on head harness "4-96"

Animation
Animation

Line art animation demonstrating the three possible filter positions