Thanks @GianLuke for your answer 
As you use exactly this equipment, I still have two questions if you don’t mind.
Do you keep the legs straight? (it can be challenging for beginners like me, but it’s certainly possible for more advanced athletes…)
And for the straight bar dips, the bar is supposed to be in front of the body so that one is lowering until chest touches the bar. If I understand you well, you do this with only one dips bar from the set of two and it’s stable enough?
Thanks again for the help 