that is a very individual question.. and no one can answer it for you really. their is no precedent that says a large rat is 90 grams to 140 grams and that an extra large rat is 140
it depends on the snake and the owner. i feed my snakes as big as "I" feel they can handle without problems. some handle larger meals better than others. i have a spider ball that prefers smaller rats even though she is big enough to handle larger ones.
its a hard question to answer for you.
experience is your only true answer.
adam jeffery
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" a.k.a. farfrumugen "
When I die, I want to go peacefully like my Grandfather did, in his sleep -- not screaming, like the passengers in his car.