Medical apparatus and instruments namely breathing tubes used for supplying air and gases to patients and exhausting air and gases from patients, and nasal cannula; ventilation and noninvasive ventilation apparatus and instruments; medical apparatus and instruments for CPAP (continuous positive airway pressure) and bi-level therapy; facial masks, oral masks, nasal masks, mouthpieces, nasal guards, facial guards, headgear, all being for medical purposes; parts and fittings for all the aforementioned goods