Solo Stove turns brown due to the natural oxidation process of stainless steel when exposed to heat. The intense heat generated during use leads to discoloration. This is normal and does not affect the stove's performance or durability. The brown color can be removed by cleaning the stove with a non-abrasive stainless steel cleaner or a mild soap solution. Wiping the stove with a soft cloth or sponge and avoiding abrasive materials will help maintain its original appearance.