Universal CPAP Headgear for Full Face Masks This universal design fits full face masks from major manufacturers like Resmed and Philips. It is compatible with the Resmed Mirage Activa offered by TEIJIN. SIZE is L. How about getting one before prices go up? This is a replacement strap/band. The head strap part deteriorates significantly due to sweat and aging, typically wearing out in six months to a year, so how about having a spare? The one photographed is for my own use, and the one I will send is new and unopened (last image). The lifespan of the head strap is about a year with normal use (without excessive force). Please consider it based on your budget. I don't think this full face mask type headgear will disappear, so you don't have to worry about buying in bulk. Full face masks have been around for over 20 years since CPAP came out. If you purchase by 4 PM, it can be shipped the next day (Kanto, Tohoku, Chubu regions).