The headgear buckle for the Swift LT CPAP Mask is a replacement rear buckle for the Swift's headgear piece. The buckle is blue, with two small vertical slits for the straps. This is a single buckle only, and does not come with any other mask parts.
This product is compatible with the Swift LT line of masks only: it is not built to attach to any other masks.
Only if it's broken. The buckle won't inherently wear out on its own, so you should only need to replace it if you lose it or if it breaks.
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