supply of gate telephone (slave telephone) for electronic lc gate, power supply system with mf battery , master telephone unit with voice logging facility-etcgate telephone (slave telephone) for electronic lc gate, power supply system with mf battery , master telephone unit with voice logging facility-etc,gate telephone (slave telephone) for electronic lc gate telephone system rdso spn tc 51/2011 latest 1.0 [ warranty period: 30 months after the date of delivery ] ] , power supply system with mf battery of 12v/24v dc (12v dc supply shall be connected to t he station telephone unit & 24v shall be fed to line circuit) with maintenance free battery for electronic l c gate telephone system [ warranty period: 30 months after the date of delivery ] ] , master telephone unit with voice logging facility for electronic lc gate telephone system [ warranty period: 30 months after the date of delivery ] ]