Receiver Unit 24V Dc Of Token Less Single Line Block Instrument As Per Rdso Specification N O.Irs S 98/2001 Amd-3 Or Latest, Carrier Frequency 1800 Hz And Modulating Frequency 65 Hz +/- 1.5 Hz To 85 Hz +/- 1.5 Hz. [ Warranty Period: 30 Months After The Date Of Delivery ] ]