This compatible, non-OEM hose adapter is required when using the SoClean 2 CPAP Cleaner with your ResMed AirSense or AirCurve 11 device to ensure a complete and effective cleaning cycle. Simply remove the lid from your current water chamber (be sure to keep the gasket and place in the new adapter lid), snap the compatible SoClean adapter onto your water reservoir, slide the reservoir back into your SoClean device, and connect the black injection tubing to the top of your newly installed adapter lid. Adapter is to be only used when using your SoClean device