Aerials; Batteries, electric; Battery chargers; Capacitors; Coaxial cables; Data processing equipment, namely, couplers; Digital signs; Ear pads for headphones; Earpieces for remote communication; Electric connectors; Headphones; Hourglasses; Light emitting diodes (LEDs); Radios; Resistances, electric; Sound transmitting apparatus; Speaking tubes; Transistors; Triodes; Vehicle radios