supply of three type windows in lhb ac coaches, lavatory window with fixed louvers and sealed glass unit for lhb coaches, as per drawing: lw54188 alt a and follow design office l.no. md35131 dated 26 / 12 / 2022 [ warranty period: 30 months after the date of delivery ] , fixed window for lhb coaches, as per drawing: lw54137 alt c and follow design office l.no. md35131 dated 26 / 12 / 2022. [ warranty period: 30 months after the date of delivery ] , emergency openable window, as per drawing: lw54138 alt d and follow design office l.no. md35131 dated 26 / 12 / 2022 [ warranty period: 30 months after the date of delivery ]