The Alstom Metropolis C830 is the first generation of communication-based train control (CBTC) electric multiple unit rolling stock in operation on the Circle line of Singapore's Mass Rapid Transit (MRT) system since 2009.

The C830 is fully driverless under normal circumstances, using CBTC which does not require traditional "fixed-block track circuits" for determining train position.

Recent studies consistently show that CBTC systems reduce life-cycle costs for the overall rail property and enhance operational flexibility and control.

Individual cars are assigned a four-digit serial number by the rail operator SMRT Trains.

A complete three-car trainset consists of one trailer (T) and two driving motor (Mc) cars permanently coupled together.