How To Disassemble The ResMed Mirage Quattro?

Start by separating the tubing from the mask.
Hold the lower headgear and unclip the clips, then unhook the straps of the upper headgear.
Squeeze the cushion clip and push the upper side tabs. Pivot the headgear away from the mask, and gently remove it. It is not essential to remove the clips of the headgear
Now, take out the mask assembly from the mask frame. Instead of pulling the elbow straight off, it is easier to swivel the bottom of the elbow.
From the elbow, disconnect the valve clip.
Without tugging on the membrane, strip off the clip from the valve.
Remove the elbow from the swivel.
For the next time you use the mask, make a note of the dial position.
Unscrew and remove the dial, then take the front of the frame away from the mask.
Remove the front support pads from the forehead support.
Remove the cushion from the cushion clip.
Remove the mask frame port caps.