kawazey 0.5M Rubber Gas Mask Hose with Fabric Protection for Connection with The Filter Boxes and Gas Masks(Black)

It connects to agas mask but I haven't boughten the gas mask part yet.

Good quality. Son bought as an add on to a vintage gas mask as part of a history project. Looks exactly as seen.

Just as the title says the gas mask line isn’t for 40mm nato it’s actually for the eastern block style of gas masks (the thread type escapes me atm). It fits perfectly in a gp-5 gas mask but not other nato style gas masks that I’ve tried.

Well, should have expected it when I ve seen the price

I wasn't really sure what to make of this unit, but there weren't many options in this price point.I was trying to figure out how I was going to test it to make sure it was absolutely airtight but that turned out not to be an issue because the female thread will not screw all the way down on the threads of any of my 3M 40 mm PAPR components for my PowerFlo. Without being able to screw all the way down, it's not possible to get an airtight connection. So there's nothing to test. It's not airtight on my components. It's only the female end that won't connect all the way, the male end will. And the tube's own connectors will screw all the way down to each other.Even if it had been able to thread all the way down, the fact that it's held together with zip ties does not inspire confidence. This hose seems more appropriate for, say, bondage play rather than actual respiratory protection.