Rule of thumb is, prey item as thick as the thickest part of their body. Now, whether you are aware or not, that snake is built to take something the size of a small rat at that size. Their jaws stretch enough to take in something three times, or more, the size of their head. No, I'm not saying you should try it. That could be harmful to the young'n, and simply not to bright
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As others have said, something a tad larger than the thickness is OK. A small bulge won't hurt, just fill it up a bit
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JMHO
Quig
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