Operational Overview for the HD35 Power Wash Trailer System from Power Line Industries, Inc. The 35HP power wash trailer system package is engineered for the professional contractor or facility manager that needs to get production power wash cleaning finished fast! Features our Industrial Duty hotcoldsteam 35 HP dual gun power washer mounted on our super duty, custom built tandem axle diamond plate trailer. It gives plenty of power combined with the legendary reliability of Power Line Industrial Series pressure washer.