D.H.S. Posi-Lock Folding Leg Bracket for Wall Mounted Work Bench / Fold Down Table (2 pcs.)

what size table legs (not length) does it hold securely?

Are these suitable for legs on a folding outfeed table for my table saw?

How much weight will they hold. For instance, could I make a fold down chair. Would it support an average sized male?

So there isn't a left and a right? The unlocking mechanism (button/latch) is on the same side of every bracket? Thanks in advance!!