Fisher & Paykel's ErgoForm headgear is supplied with all F&P Simplus Full Face CPAP Masks. Made of breathable stretch fabric, ErgoForm Headgear is designed to self-locate high on the rear of the head to allow for maximum head movement without dislodgment. Special stretch and non-stretch panels on the headgear provide support and structure for improved performance; while embedded Velcro Tabs and Easy-Clip Hooks allow for easy fitting and removal without constant adjustments. Two headgear sizes are available: All Small Sim---plus masks come with Small Ergo---Form Headgear. All Medium and Large Sim---plus masks come with Medium/Large Ergo--Fit Headgear. Either size headgear can be used with any Sim-plus CPAP Mask. PART NUMBER(S)400HC582 (Small), 400HC583 (Medium Large) MATERIAL Not Made with Natural Rubber Latex.