The Panorama Nova Z/ZS/ZST are designed for use with closed circuit breathing apparatuses (e.g. BG 174). The Panorama Nova Z mask is designed for an operating period of up to 90 mins. The Panorama Nova ZS & ZST are designed for use over 90 minutes. The ZS & ZST are equipped with visor wipers inside the mask which can be operated using the lever on the outside of the visor. The ZST is equipped with a communications input.