Patient interface with an occipital anchor

A patient interface comprising:

• a plenum chamber pressurisable to a therapeutic pressure of at least 6 cmH2O above ambient air pressure, said plenum chamber including a plenum chamber inlet port sized and structured to receive a flow of air at the therapeutic pressure for breathing by a patient;
• a seal-forming structure constructed and arranged to form a seal with a region of a patient's face surrounding an entrance to a patient's airways for sealed delivery of a flow of air at the therapeutic pressure throughout a patient's respiratory cycle in use, said seal-forming structure having a hole therein such that the flow of air at said therapeutic pressure is delivered to at least an entrance to a patient's nares, the seal-forming structure constructed and arranged to maintain said therapeutic pressure in the plenum chamber throughout the patient's respiratory cycle in use;
• a positioning and stabilizing structure to provide a force to hold a seal-forming structure in a therapeutically effective position on a patient's head, the positioning and stabilizing structure comprising:
• a gas delivery tube formed as a continuous structure to receive the flow of air from a connection port on top of the patient's head and to deliver the flow of air to the entrance of the patient's airways via the seal-forming structure, the gas delivery tube including a pair of tabs constructed and arranged to contact, in use, at least a region of the patient's head superior to an otobasion superior of the patient's head, wherein each tab of the pair of tabs having an opening with an opening length;
• a pair of removable arms removably coupled to the tabs, each removable arm constructed and arranged, in use, to extend in a posterior and inferior direction, each removable arm comprising:
• a first end including a clip configured to be removable from one tab of the pair of tabs, wherein the clip includes a clip length that is less than the opening length, wherein the clip is configured to move along the clip length and/or pivot within the opening in order to adjust a force vector, and
• a second end opposite to the first end;
• and
• a vent structure to allow a continuous flow of gases exhaled by the patient from an interior of the plenum chamber to ambient, said vent structure being sized and shaped to maintain the therapeutic pressure in the plenum chamber in use,
• wherein the patient interface is configured to allow the patient to breathe from ambient through their mouth in the absence of a flow of pressurised air through the plenum chamber inlet port, or the patient interface is configured to leave the patient's mouth uncovered;
• and
• wherein each removable arm of the pair of removable arms includes at least one bendable segment configured to allow positional adjustment between the first end and the second end to impart adjustment of a force vector, and wherein each bendable segment includes a plurality of bendable sections that are independently adjustable to adjust internal arm angles by moving one or more of the plurality of bendable sections.