This is an oddball Jack Kirby piece I've looked at here before. Below is some pencil artwork which seems to be a tryout of sorts for the cover image above. It feels like maybe this was a wraparound cover at one time, though that is speculation. Though if that is the case, the figure of the hero would look more like the other 3-D cover heroes, bursting out of the frame.
Note how the hero Stereon has a somewhat different chest emblem. Here's a look at a sample page.