This is a fictional device found in Frank Herbert's Dune series of books.
A stillsuit is a body enclosing garment that was invented on Arrakis. The stillsuit allows the wearer to travel in the desert, while losing as little mositure as possible (this is important because Arrakis is a desert planet, and water is a very scarce resource). Its fabric is a micro-sandwich performing functions of heat dissipation and filter for bodily wastes. Reclaimed moisture is made available by a tube from catch pockets.
The skin-contact layer is porous, allowing perspiration to pass through it, almost like the normal evaporation process. The next two layers have heat exchange filaments and salt precipitators.
Motions of the body, including breathing and some osmotic action provide the pumping force. Urine and feces are processed through thigh pads.
In the open desert, one wears a filter across the face and a tube in the nostrils with plugs, to make sure it fits tightly. One must breathe in through the mouth filter , and breathe out through the nose tube.
The best stillsuits are made by the Fremen, although there are a few other manufacturers who try to emulate the Fremen technology, but these stillsuits are noticably of inferior quality.