Spacesuit requirements

Several things are needed for the spacesuit to function appropriately in space. It must provide:a stable interior pressure. This be able to less than earth's atmosphere, as there is usually no need for the spacesuit to carry nitrogen.
breathable oxygen: Usually a rebreather is used beside with a supply of fresh oxygen.

temperature regulation: Heat can only be missing in space by thermal radiation, or conduction with objects in physical contact with the space suit. Since heat is missing very slowly by radiation, a space suit almost always has only a cooling system and heavy insulation on the hands and possibly feet