The Model C was the improved version of the Model B.
The Model C was a muzzle gas mask, very similar in shape to the Model B. The mouthpiece was made of metal and and had a rubber edge, therefore it was tighter.
The Model C was the first Dutch gas mask to have changeable filters, it had a little cartridge on the front that could be changed.
The kit consisted out of the mouthpiece, goggles and canister. The manual would be on the inside of the canister.