The Hose Accessory For Gas Mask will fit standard 40mm threads and measure about 13 inches. One end of the hose threads into the gas mask and the other end threads onto the filter. These hoses are brand new and unused hoses so they fit on to all Israeli and Russian gas masks. It will also fit Finnish gas masks but does require the thread adapter. Go all the way with the military disguise with the Hose Accessory For Gas Mask.