The classic JSA version of Al Pratt was a short guy with a scrappy attitude who acquired an Atomic Punch after an explosion featuring the villain Cyclotron. Cyclotron who also wound up being the grandfather of Atom Smasher, while Al’s DNA was used to create Damage.
Why does this matter?
Because in Earth 2, the Atom is the best of all three worlds. You have Al Pratt, the short and scrappy soldier for the World Army, seemingly with his Atomic Punch, wearing a color scheme matching the last one we saw Damage wear…oh, and he has the size change powers of Atom Smasher.