ISO 22196 certified; antimicrobial tube eliminates up to 99.99% of bacteria. 15mm internal diameter. 22mm cuff provides universal fit for standard CPAP machines and masks. Slimline tubing creates less weight on the CPAP mask and machine. 6 foot tubing length provides sufficient range of movement. Made from polypropylene with an antimicrobial additive. Blue and clear in color.