SMRT first attempted to install a passenger information system SMRTime on trains using LCD displays in 1999; these have since been removed. In November 2006 the doors of three cars (carriage number 3006, 1006 and 2006) were installed with a dynamic, in-train system displaying station information for testing; these are similar to ones used by Hong Kong's MTR. An initial prototype of STARIS based upon the existing Automatic Transit Info System was developed in-house; this was removed before the end of the year without entering service.