I decided to make myself an air filter mask for Steam & Cinders [link]
, a Steampunk Larp in MA that I go to. This is the result! It is made from 6/7 oz veg tanned leather, with brass plating, a sueded pigskin lining, and a built in filter!
To make it more comfortable to wear around the neck for long periods of time and to ease putting on when needed I made the straps capable of swinging.