supply of 1) master telephone unit with voice logging, 2)slave telephone for electronic lc gate 3)centralized power supply unit 24/12volts1) master telephone unit with voice logging, 2)slave telephone for electronic lc gate 3)centralized power supply unit 24/12volts,master telephone unit with voice logging facility for electronic lc gate telephone system as per specification no. rdso/spn/tc/51/2021 rev 1.0 or latest. [ warranty period: 30 months after the d ate of delivery ] ] , slave telephone for electronic lc gate telephone sysytem as per rdso spn no. rdso/spn/tc-51/2021 rev 1.0 or latest with surge protection and line connection unit. [ warranty perio d: 30 months after the date of delivery ] ] , centralized power supply unit 24/12volts dc with 7ah battery for electronic lc gate teleph one system as per rdso spec.no.rdso/spn/tc/51/2021 rev.1.0 or latest. [ warranty period: 30 months after the date of delivery ] ]