These high-quality mouthpieces can be easily inserted into the breathing unit of the metabolic analyzer. Thus, the metabolic analysis is ready for use within a very short time for each individual subject. In each set there is 1 mouthpiece (round, white) and 1 nose clip, so that the measurement can be performed hygienically and easily. This consumable is compatible with the current model of metabolic analysis, with the metablicscan.