Yellow Line and Pink Line are major monorail lines in downtown Bangkok, which are planned to be put into operation by the end of 2021. Among them, the Yellow Line is planned to extend about 30 kilometers with 25 stations and a depot. The Pink Line is planned to extend 34 kilometers with 30 stations and a depot. The public bidding of the project was initiated by Bangkok government MRTA for social investors, and BSR, the consortium comprised of BTS, Sino-Thai and Ratch won the bid. The vehicles will adopt the world's advanced fully autonomous unmanned technology. The first train will be delivered by the end of June 2020, and the rest will be delivered by 2021.