On June 5, 2008 (May 2, 2008 in the lunar calendar), the last DK11 train of the Beijing Metro was retired. DK11 train data map The train on the left is DKZ4, the middle is DK3, and the right is DK11. On June 5, 2008, the last DK11 train on the Beijing Metro was retired and is currently all replaced by SFM04 air-conditioned subway trains. The DK11 subway electric bus was converted from the DK2 bus by the Beijing Metro Rolling Stock Factory from 1984 to 1985. It's a chopper regulating vehicle.