Replacement headgear for the Respironics WISP Nasal Mask. Please note: The Respironics WISP Nasal Mask and Headgear is sold with the Standard (1094082 size headgear. If you require a size larger than the original standard that comes with the mask, the Large (1094078) is the size for you. Sizes Available: 1094082 - Standard 1094078 - Large You should order the large headgear if: Your dress shirt collar size is greater than 17 inches and/or Your hat size is greater than 7.25