SeaWind Immersion Suits are announced as "the world's first ... to be approved for helicopter transport, shipping, and work use."
They are triple certified by SOLAS, ISO, and EASA. Its emergency breathing system is integrated in the SeaLion Europe lifejacket with which it is to be worn. It makes breathing underwater possible and has a floating buddy linke hook.
SeaWind is designed for optimal ergonomics for freedom of movement without knee or seat restrictions. Suits weigh less than 2 kg with waterproof zips under the arms for good ventilation. Additional SeaWind details are yours free.