The BLUE team has no external filter, but has a rubber piece inside the mask that covers the nose and mouth (you can see this in the movie stills) and an air line that leads to special mini oxygen tanks, which is vital for anyone who is temporally inverted. This item does not include the airline or hose attachment. The helmet appears to be a version of a flight deck crew helmet. I believe the cloth portion of the helmet may have some subtle additional coloration to it to give it the appearance of age. There is also some real dust and dirt on there, presumably from the many weeks of shooting out at Eagle Mountain, where the final battle was filmed.
The style of ear protection varied amongst the costumes, so this small detail may or may not match the "hero" version you see the main stars wearing, but rest assured they are all from the same lot. The Mask is model CM-6F1, manufactured by Mira Safety. They sell a version of this mask for retail customers.
You should expect to see some surface scratches on this item, there was a lot of stunt work done out at the filming site. Be the hit of your next halloween party, comic-con, paintball war or temporal pincer, I haven't seen any other sellers with this item!