invalid and patient convenience and handling equipment, namely crutches and structural parts therefor, canes for medical purposes, tub transfer benches, bath and shower seats, grab bars and poles, male and female urinals, bed pans, invalid walkers, foam and pnuematic cushions, pads and protectors for therapeutic use, blanket supports, medical pillows, emesio basins, portable ramps, armrests and back rests, patient lifting and handling devices; respiratory apparatus, namely oxygen concentrators, conserving units, reservoirs and delivery apparatus for medical applications, nebulizers and parts therefor, respiration air flow monitoring devices, aerosol masks, continuous positive airway pressure respiratory therapy devices and parts therefor, air compressors and air filters for medical applications