On calisthenics day I do flies face down with hands in loops of a strap thrown over a joist as a warmup then static hold at full stretch and move hands toward feet to load on more bodyweight. It is looking unlikely I'll ever achieve a maltese cross. I don't know how those guys do it. Maybe they all trained on one of these.
Anyway that thing needs to be way longer. Recommend you buy 2 blocks of wood and 4 wheels instead or find an old bit of rope to throw over a chin bar.
