I agree with JM. If your retics head is as big as a softball, you will be surprised how small XS rabbits and XL guinea pigs are compared to her. Caesar's head isnt nearly the size of a softball or even half that and he eats 2XL guinea pigs like my baby boas eat weaned rats lol. You need to look at the middle of the snake to judge the food size, not the head. The owner of the reptile shop i go to has a bunch of mainland retics and she feeds them adult rabbits. She showed me a few of them and let me tell you, an adult rabbit is pretty big lol. These are for her 14+ foot retics.