Personal emergency response communication apparatus is a new and useful improvement for pager to access 911 system to call for help (Police, Fire Department and Paramedic). Equipped with a preprogrammed switch to 911 system, a micro computer chip for memory, mini speaker, microphone and an antenna. Upon...http://www.google.com.hk/patents/US5894591?utm_source=gb-gplus-share專利 US5894591 - Personal emergency response communication apparatus for pagers
