The Javelin-7 was a hyperspace capable ship designed and engineered by Batman for use by the Justice League. The vessel was designed to Earth-Space transit for members of the League who couldn't traverse the vacuum of space. It was capable of both space and underwater travel. Several were lost in the line of duty.
After the League was expanded, new Javelins were designed, and several were stored in the hangar bay of the Watchtower.
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