Function Introduction Adopting an adjustable respirator, and low breathing resistance, the air supply can be self-adjusted according to the user's requirements. Side seals are standard, in a B-shape structure, which can be connected around the umbilical cord on the diver's shoulder. The communication connection is a watertight plug. The mask housing is a high-strength polycarbonate composite material with an integral exhaust valve and mask. The neoprene headgear, which keeps the diver warm and holds the headset, is secured to the mask by stainless steel straps. The five-pronged headband, made of hard-wearing natural rubber, fits over the headgear and ensures a tight seal on the mask.