Megaphones; Acoustic couplers; Components for electrical mains in the nature of electric wires, cables; Electrical plugs and sockets; Loud speakers; Metal alloy wires for electrical fuses; Record players; Resistances, electric; Vacuum tubes for radios

Optical apparatus and instruments; eyepieces; eyewear; optical apparatus and instruments for blocking light; optical apparatus and instruments for blocking light to improve sleep quality; optical shields