The HP1 BL is the Dainese First Layer specifically designed for those who wants to push past their limits and conceived to satisfy the needs of most demanding skiers. Years of research into the dynamics of the human body have helped determine which parts of the body are never extended or contracted, despite movement. By joining these points along “non-extension lines”, the pressure placed on the body is kept constant. This research helped Dainese engineer the BIOSUIT, designed for NASA astronauts, and was the inspiration behind the structure of the HP1 BL M SHIRT/HP1 BL L SHIRT. Seamless technology and the Dryarn fabric are combined togheter to provide great insulation with maximum breathability, coolness and comfort. Meanwhile, the “non-extension lines” guarantee a compression effect that helps keep muscles in position when skiing.