CURMIO PORTABLE OXYGEN CONCENTRATOR BACKPACK (Bag Only, NOT includes machine and accessories.) Dimensions 9.8”x 4.7”x 11”. Heavy duty nylon material ensures years of frequent use. Compatible with Inogen One G3/ G4/ G5, Philips Respironics SimplyGo Mini, OxyGo FIT/ NEXT and Caire FreeStyle Comfort Units. Protective bungeecord inside to secure unit in place. Mesh panels around for optimal ventilation and heat dissipation. Thick padding on the bottom provides adequate cushion and helps the oxygen machine stand up on flat surfaces.