Headgear (30) for fastening a non-invasive interface device (20) to the head of a user, the headgear (30) comprising means for attaching the headgear (30) to the interface device (20), and first and second support members (33,35) adapted to extend about the head of the user, in use, wherein the first and second support members (33,35) are defined by a continuous member (32) that cooperates with at least one adjustment component (40a,40b) to also define an adjustment loop (34), and adjustment of the size of the adjustment loop (34) enables the sizes of the first and second support members (33,35) to be varied.
