I can see the grey cells are working full time
FLOAT connects rod and base ends to tank allowing free oil flow to tank in both directions. Pressureized oil from the pump contines uninterrupted to power beyond - e.g the 3pt valve.
Contrast that to DOWN where tank is not used. Instead pressurized oil is diverted to rod end and pressurized return oil is sent to power beyond - e.g the 3pt valve.
Mull on that a bit and you may see a method in my madness.
Dan
PS - I suspect a coupler and the goal is to identify which one(s).