The cylindrical miniature-LED light-emitting device. The device is provided on a front end of a metal cylinder thereof having therein an LED assembly and a battery assembly with a socket to receive the LED. The LED assembly is constructed from the LED and a push switch is mounted in the metal cylinder....http://www.google.ca/patents/US6777890?utm_source=gb-gplus-sharePatent US6777890 - Cylindrical miniature-LED light-emitting device
