The Boost feature was added to the Inuheat App to give the user an extra 5 minute shot of “bonus” heat when even the highest heat setting isn’t keeping you as comfortable as you would like in extreme conditions. We limit this setting to 5 minutes to make sure that you don’t get overheated and cause any potential harm to your skin due to excessive heat. It is an optional feature and should only be used in very cold conditions as needed.