scientific, nautical, surveying, photographic, cinematographic, optical, weighing, measuring, signaling, checking, supervision, life-saving and teaching apparatus and instruments, namely, scales and balances, fire blankets, and fire extinguishers; sound or video recording or reproducing apparatus and instruments, namely, sound and video recording and playback machines, home theatre systems comprising DVD players, audio amplifiers, and audio speakers; appliances for recording and reproducing s...