The K3 is listed on their site as B-Stock. Last time I checked with Axe this usually meant open box return merchandise or floor demo. It also may be a discontinued sub model.
Your best bet is to phone up Axe on their 800 number and talk to Brad. That guy's been answering the phone for their web orders for years He'll be able to tell you what exact differences there might be and possibly give you a better idea of the condition.