O2totes Ultra LightWeight Backpack Fits The Inogen One G4/OxyGo Fit/Lightest Backpack for The Inogen One G4, under 10 ounces

O2totes Ultra LightWeight Backpack Fits The Inogen One G4/OxyGo Fit/Lightest Backpack for The Inogen One G4, under 10 ounces WILL ONLY FIT THE INOGEN ONE G4: IO-400

Inogen Extended (8-Cell) Battery - Replacement Battery - for The One G4 Rove 4-1.1 lb. - 5.91 x 2.68 x 1.34 in.

Inogen External Battery Charger - for Rove 4 and Inogen One G4 - Portable Oxygen Device Battery Charger - 0.12 lbs. and 3.13 in. W x 2.75 in. L x 1 in. H