The Rubber Ducky antenna is an electrically short antenna which functions somewhat like a base-loaded whip or monopole antenna and is sealed in a rubber or plastic jacket to protect the antenna. Electrically short antennas are often used in portable equipment because a one-quarter wave-length element, necessary for resonance of a linear element over a ground-plane, is often too long for convenient portable operation. Many years after its invention in 1958, the Rubber Ducky antenna became the antenna of choice for many portable radio devices, including video link, walkie-talkies and other portable transceivers, scanners, GPS receivers, and any other device where safety and robustness take precedence over antenna capabilities.