Heavy duty vehicles under the door steps, including a platform body and a pedal, the bottom end of the platform body is welded in the middle of the pedal, one end of the pedal is formed with a boss,
the side of the platform body near the pedal is formed with a groove, the side wall of the platform body is formed with a bolt hole. The beneficial effect is that the utility model increases the trampled
area and trampled space of the lower door step through the design of the boss and groove, so that the driver is more stable when stepping on the lower door step, effectively avoids the phenomenon of stomping empty,
and improves the safety of the use of the lower door step.