Apparatus for testing gas, liquids and solids; Components for electrical mains in the nature of electric wires, connectors, circuit breakers, cables; Computer-controlled apparatus for testing and measuring radio frequency signals, concentrations of gas and liquids, audio signals; Computer stands specially designed for holding a computer, printer and computer peripherals; Drum units for printers, facsimile machines, scanners, copying machines and multifunction electronic devices for use in copying, printing, scanning, video capture and/or transmitting documents and images; Electronic apparatus for testing the sterility of medical equipment; Electronic point-of-sale (POS) systems comprised primarily of point-of-sale terminals, bar code readers, touchscreen monitors, keyboards, document printers, scanners, and recorded operating software; Electronic readers/recorders for medical patient identification bands; Image fuser units for computer printers comprising electro-mechanical rollers for the purpose of transferring toner onto paper; Kitchen timers; Marine radio communication machines and apparatus; Odometers; Print heads for document printers and plotters; Printer hubs; Thermal printers