Henri Lloyd seilstøvel. The Shadow Boot is a fully waterproof and breathable leather boot constructed from the highest grade leathers with Cordura panels. The boot features a Dri-Lex lining which transports perspiration away from the foot - keeping the wearer more comfortable for longer. The boots also feature a technology called Outlast which was originally developed by NASA to protect astronauts against temperature fluctuations in space. This technology stores the heat from the the foot as it warms and gives it back to the foot when it cools down.