Headgear for patient interface

An interface assembly for use in providing a breathing treatment, the interface assembly comprising:

• a mask, the mask comprising a frame and a seal supported by the frame;
• a headgear connected to the mask;
• and
• a break-fit assembly configured to selectively lengthen a loop defined by the mask and the headgear when a predetermined force has been exceeded and return the loop to a use length when the predetermined force has not been exceeded;
• wherein the break-fit assembly comprises a mechanical coupling that resists elongation from a first length to a second length until a force is applied that exceeds the predetermined force, wherein the mechanical coupling comprises a first component, a second component, and a biasing member, wherein the first component and the second component are joined by the biasing member, and wherein the biasing member creates a return force between the first component and the second component when the break-fit assembly elongates from the first length to the second length.