General: The new `WIN TECH 275 Challenger` twin chamber lifejacket was developed for the off-shore industry in collaboration with international safety products and wind farm equipment ltd as a unique derivative of the ISP challenger lifejacket. This new jacket was designed for the off-shore renewable industry and offers the first of its kind in relation to integration with accompanying equipment. the twin back strap developed at present purely for the challenger jacket allows the jacket to be worn with more comfort as it keeps the neck collar clear of the head allowing a full range of movement. This is vital with the off-shore wind industry as when climbing structures it allows the wearer to look up and down without any pressure to the neck. The other key feature is that this is the only lifejacket specifically designed to allow access to the rescue dorsal plate on the rear of a fall arrest and working at height harness. All other lifejackets prevent access to this harness strong point because of their design. The challenger jacket also features webbing radio fastening so when worn in conjunction with the win tech constant wear transfer suit there is good access to the individual’s radio. This jacket is designed to be used with externally mounted beacons such as the mcmurdo 406KHz S220.