A lot of people use KY jelly.
But my personal preference has been good old fashioned H20.
I just make sure both the probe and the vent area are good and wet. (I use distilled water)
Distilled water has a safe Ph....and there are no chemicals present in it. Water is not thick like KY....so sperm should have no trouble navigating through it on their adventurous journey...lol.
While that last (silly) statement may only be of importance if you are pairing the snake shortly after confirming it's gender....I prefer not to introduce anything foreign to that important end of the animal.
So anyway, I have always used distilled water. It works fine and certainly provides adequate lubrication. Keep it simple.
There's not need to fret....just get it wet!

Your friend,
Harlin Wall - WALL TO WALL REPTILES!
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