Fisher & Paykel's StretchGear Headgear is a comfortable and breathable elastic headgear, specially designed to maintain a firm seal. This headgear is compatible with all Zest and FlexiFit series CPAP/BiPAP Masks including the FlexiFit 405, FlexiFit 406, FlexiFit 407, Zest, Zest Q, and Lady Zest Q.