therapeutic and diagnostic equipment-namely, [ electrocardiographs, ] cardiac monitors, defibrillators, and synchronizers for use with defibrillators, and parts thereof and accessories therefore; external defibrillators and battery packs therefor; patient monitors for monitoring cardiac, pulse and blood pressure functions; [ electrocardiograph artifact filters; cardiac stress testing and rehabilitation systems comprised essentially of treadmills and programmable treadmill controls; spirometers; telemetry electrocardiogram apparatus, composed primarily of radio transmitters, receivers, monitoring scopes and computers; and electrodes, electrolytes, wires, cables, leads, and recording paper for use in connection with all of the foregoing ]