Cochin Shipyard Limited (CSL) has signed contract for building high-tech, off buoy tender vessel (BTV) for the Directorate General of Lighthouses & Lightships. The contract documents were signed by Capt AM Surej, director general, DGLL, and P Vinayakumar, director - technical), CSL last week. The multipurpose vessel is used for transporting and placing buoys in positions at deeper depths, recovering buoys and their moorings for examination and overhaul, attending on their lighting equipment, towing and mooring of light vessels and distress management, etc.