supply of 4 sq mm (equal qty. in black , blue , red , yellow colour) single core thin walled electron beam irradiated copper cable.4 sq mm (equal qty. in black , blue , red , yellow colour) single core thin walled electron beam irradiated copper cable.,4 sq mm (equal qty. in black , blue , red , yellow colour) single core thin walled electron beam irr adiated copper cable with copper conductor working voltage above 750 v and upto 1.8/ 3.0 kv suitable for rolling stock application as per rdso specification no elrs/spec/elc/0019 rev.4 of feb 2018 or latest .make- rd so approved sources . [ warranty period: 30 months after the date of delivery ] => limited