The trailing end of a District Railway G Stock driving motor (DM) car as delivered in 1924 showing the original arrangement of the couplings.  The main and train line hoses are under the coupler.  Under each side of the headstock there is a set of power busline, control and lighting control jumper sockets.

Because of this arrangement District cars were not "handed" at this time like tube cars and could couple either way round.  This arrangement only lasted a few more years.  New stock delivered in 1927 had tube style "handing" and air hoses were mounted on the waist panels.

Note the leather covered safety chains on the body corner.  These were hooked over the gap between cars.   They were not used after 1927.

The only difference between this and earlier cars, as far as coupling was concerned, was the movement of the lighting control cable from roof level to below the headstock.  A connector is provided on this stock over the end door to allow it to coupler to older cars.