![background image](http://html1.mh-extra.com/html/caire/helios-marathon-h850/helios-marathon-h850_use-manual_3343065055.webp)
Product Specifications
HELiOS Marathon
TM
H850 Portable Oxygen Unit Home Use Guide
51
7 Product Specifications
Operating Environmental Specification
-20 °C to 40 °C (-4 °F to 104 °F)
95% maximum relative humidity
Storage Environmental Specification
-40 °C to 70 °C (-40 °F to 158 °F)
95% maximum relative humidity