No precise one answer to that, but MANY!

They males usually always switch sides with each successive copulation, staggering the use of each hemipenis. This is also something that MANY people aren't even aware of. Make sure the enclosure has a cooler side in the mid to high 70's and a warmer side around the mid 80's for proper digestion (if the males even want to eat at this time that is). Temps that are too warm can kill male's sperm.

~Doug
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"a snake in the grass is a GOOD thing"

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