I just opened my tailgate & pulled out the Debo Step, pix to follow.
I measured the sidewalk to the top of the tailgate when opened its 32"
the sidewalk to the step itself is 16"
then i stepped up on the Debo Step with 1 foot, placed a hand on the trucks bed rail & then stepped up onto the tailgate, it was fairly easy even for me.
Then i stepped off the tailgate & down onto the step & then down onto the sidewalk, it was a bit harder on my old legs, but a person can do it. Of course it would be even easier if i had been 5' 10" or taller.