I'd say that's a sinaloan. I just got one too (scroll down past the first animal):
http://www.angelfire.com/home/thaneshomepage/snakes.html
Not that there's a lot of difference other than the spacing and width of the red bands. Between nelsons and sinaloans that is. Nice snake though. Mine will be nice too when it gets bigger. Been a long time since I've owned any milksnakes. This is what I call the little "jewel". To offset the monster I have 
>Hi...I'm new to this group. I just got my first Milksnake on Sunday. Unfortunately, I got it from a chain store so I don't have any history. I believe it is a Nelson's Milk? I have no idea on his age or sex for that matter. I do know that he is beautiful, very friendly and has eaten his first meal (for me) already. Also, he is very active and loves to climb and burrow. Any comments or suggestions would be greatly appreciated. Thanks in advance!
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Thane