The mass of approximately 6,000-kg supported a habitable internal volume of 14-sq m. It also has external unpressurized storage. Like SpaceX's Dragon 1 spacecraft, the HTV would approach the International Space Station, before being berthed by the station's robotic arm.
The HTV was unique in that it was the only spacecraft that had the capability to transport International Standard Payload Racks, whether to International Space Station or from it. These racks are a standardized way to integrate equipment or experiments into the station.
