 Also known as a "Jersey upline", an upline is a line deployed by the diver, and fixed to the bottom, usually on a wreck, to serve as a position and depth control during offshore ascents in moderate currents, where the diver wants to prevent excessive drift during decompression.The bio-degradable natural fibre line is carried on a spool and deployed connected to an inflatable decompression buoy or lift bag at the end of the dive, and the bottom end tied off to the wreck.After completing decompression and surfacing, the diver cuts the line free at the buoy, and the line sinks and naturally decomposes over a few months.