Externally identical to the 9V 71427 motor (shown previously),
this motor is almost one-third lighter at the expense
of slightly reduced speed. The difference in weight makes it
more sought after than the original 71427 motor, so it sells
for significantly higher prices. The motor has a 1L axle and
connects to the power supply through a 2×2 contact area
on its top. Its upper surface is conveniently shaped with one
recess for the power plug and another for routing the wire
backward. Its lower surface has a one-plate-tall 2×2 bulge
in the back. Just like the 71427 motor, this motor can be
mounted on rails using the two slots on its sides (shown in
Figure 12-3).