Check this post for some help on that topic: http://www.ball-pythons.net/index.ph...ight=het#18026

100% het means it is definitely heterozygous for the trait, in this case albinism, which means either one parent was albino and one was normal or het OR it's been bred to another snake and one or more albino hatchlings resulted.

66% het means that both parents were 100% het and this one is normal-looking rather than albino, so you have a 66% chance of its carrying a gene for albinism.