Racks and mountings specifically adapted for use with scientific, nautical, surveying, photographic, cinematographic, optical, weighing, measuring, signalling, checking in the nature of supervision, electronic home security, electronic office security, namely, racks and mountings specifically adapted for use with audio, visual, computer and/or telecommunications equipment, namely, audio amplifiers, audio mixers, audio/visual special effects units, graphic equalizers, electronic video signal s...