It looks like this type: http://www.amazon.com/Alvin-Co-DRAFT-MATIC-PENCIL/dp/B001DKI...

But that's just me doing my best to read the side of the pencil in the photo, but it looks like the one!

I had the same reaction upon seeing that photo. My dominant hand has been in a cast for four months, so I've become left handed. The new dominant hand is rather picky about writing utensils, and this one looks like it fits the bill nicely.