trucks used in truck terminals or marine ports -- a. K. A. "yard dogs" are ideal for retrofit hybrids. Yard dogs often average less than 3 miles per gallon and are frequently over-the-road tractors, near the end of service life. Such vehicles are not well maintained and have extremely high emissions relative to miles traveled. The company is in the initial stage of designing a yard dog with hybrid electric or 100% electric drive system. Call or e-mail for more information.