ResMed AirFit N20 Mode D'emploi page 5

If necessary, slightly adjust the position of the mask for the most
comfortable fit. Ensure that the headgear is not twisted and for the AirFit
N20 the cushion is not creased.
1. Turn on your device so that it is blowing air.
Adjustment tips:

To resolve any leaks at the upper part of the mask, adjust the
upper headgear straps. For the lower part, adjust the lower
headgear straps. Adjust only enough for a comfortable seal.

The upper strap adjustment is the key to seal and comfort.

Do not overtighten the lower straps because they mainly serve to
keep the cushion in position.
Removing your mask
1. Twist and pull both magnetic clips away from the frame.
2. Pull the mask away from your face and back over your head.
Disassembling your mask for cleaning
If the mask is connected to your device, disconnect the device air tubing
from the short tube.
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