7700 Series Half Mask RespiratorsComfortable half masks are suitable for multiple work environments and can be adapted to PAPR or Supplied Air systems. Because of low "dead air" space within the mask, less exhaled air is recycled. Strategic placement of the exhalation valve means that more breath leaves the mask swiftly, creating a cooler environment for the wearer. 7700 series half masks are 100% silicone, making them an ideal solution for workers with latex allergies. Dual-elastic headstraps are carefully engineered; bottom straps have more elasticity than top straps to create a secure, non-slip fit. Wide, contoured sealing area provides an improved fit for a variety of facial types. Respirator Type: Half-Face Mask.