The ResMed AirFit F40 Headgear is a genuine replacement headgear designed specifically for the AirFit F40 Full Face CPAP Mask. Engineered for a secure, comfortable fit, it keeps your mask in place throughout the night without over-tightening. Available in Small, Standard, and Large to suit a wide range of head sizes. Features: Genuine ResMed Replacement - Designed and manufactured by ResMed specifically for the AirFit F40 Full Face Mask, ensuring a perfect fit and optimal performance. Secure, Comfortable Hold - Soft, breathable fabric maintains a firm seal without excessive pressure, reducing marks and discomfort during sleep. Easy to Adjust - Simple strap design allows quick adjustments for a personalized fit, even in the dark. Multiple Sizes Available - Available in Small, Standard, and Large to accommodate a wide range of head sizes.