I tried to research this mask, but I could not find another one like it or any information on it.  It has a leather skin with a "windshield" style insert to see through.  The elastic and canvas/fabric holds the mask to the face.  There is a hole that is stuffed with a sponge material.  I'm not sure if a hose once attached to that area or if the sponge was the only "filter" for the mask.  There is also a Patent number of 01736 Sept. 1 '86 stamped in the leather.  Could be 1886, but the early Patent number suggests it could be as early as 1776.  The last picture shows a similar patent that I found online that "may" portray how it was intended to be used.

Mask was most likely designed for firefighters/firemen.  

Please see photos for best idea of condition

Happy to combine shipping

All items come from a smoke free/pet friendly home