That's a very early example, almost certainly early 2007 as the seller states. The all-black hub motor and "flames" rim decals gives the clue to it's age. Another indicator is the "nutcruncher" brake cable guides on the top of the top-tube. It may be a trick of the light, but also notice the "gimp" in the top-tube. That machine would have originally been fitted with a Lishen 13ah battery. I have an early '07 905 which I'm refurbishing, the Lishen battery of which has lost 13% of it's original capacity, but it's still good for 25 miles restricted.
As already noted, the battery casings are identical but, the kettle plug on later examples have the ground pin arse-about-face to stop people plugging it into the mains. I'm pretty certain that machine has been fitted with a new Advance 14ah battery to replace the original Lishen. Providing the price is right, not a bad buy.