Is this too big for my 5 month old male ball python?
Yeah it looks like he could take down two of those lol. Is it a hopper? One of the biggest feeding mistakes new ball owners (myself included!!!) is underestimating the size of prey they can take. It's amazing how wide they can open those little jaws. Like others have said, give it something that's the same or just a tad bigger than he is around. Or if you have a scale, 10-15% of body weight.