Well I'm a bit new to owning the scaley babies. My little boy ate a large rat fuzzie. The new local store I found has 'large fuzzies' and 'small fuzzies'. I gave him a one of the large 'small fuzzies' last weekend for his first meal since having him and he took it like a champ. When I weighed him before that he was only 206g. After eating and passing it 3 days later he'd put on 10 whole grams! So if you're unsure you could always ask your store for a rat fuzzie on the larger side or see if they have a pup that's on the smaller side. Usually they're really accomadating about things like these and understand the odd little 'tween' stages of growing. Good rule of thumb as almost everyone says is no wider than the thickest part of the belly, their heads and necks may look super tiny but they can take a mouthful. (Bad pun intended).