Our DCARB Fleet Program uses our D100, a smart device that enhances vehicle efficiency. It’s attached to vehicles, powered by their batteries, and generates hydrogen from tap water on demand. A flat monthly subscription fee per unit, which will be less than your fuel savings.   No upfront capex or fitting fee. If you are unhappy with the service at any time, you return the unit to stop the subscription at any time, for any reason, at no cost.