SR 550 Breathing hose 0,9 m, PU are tested and approved together with the following products, and are intended for use with Sundström SR 500, SR 500 EX and SR 700 battery-powered fan units; SR 200 Full face mask and SR 200 Airline compressed air-fed mask. SR 550 Plastic hose made of PU with durable spring steel spiral. Chemical-resistant. The hose are delivered complete with couplings.