Respiratory products for medical purposes, namely, aerosol therapy products in the nature of compressors, nebulizers and accessories, aspirators, compressed oxygen systems primarily comprised of oxygen cylinders, regulators, conserving devices and refilling units, liquid oxygen systems primarily comprised of oxygen dewars and portable oxygen dispensers, oxygen concentrators, oxygen conserving devices in the nature of demand, variable, volume and fixed volume devices, nebulizers, nebulized compressors for respiratory therapy, patient monitoring systems primarily comprised of pulse oximeters and capnometers, sleep therapy products in the nature of positive airway pressure devices and accessories therefor, portable demand oxygen delivery devices for respiratory therapy; medical devices, namely, oxygen and aerosol masks, oxygen and aerosol tubing and tubing connectors, oxygen nasal cannula, oxygen regulators, oxygen cylinders sold empty; oxygen cylinder accessories, namely, valves, carrying cases, storage racks and transport carts