This was a gift, so I haven't had it authenticated. I've worn it once or twice, so I think it's in good condition. There's no box or warranty, so please only purchase if you understand that it may be a parallel import or a counterfeit. I want to sell it, so I don't intend to have it authenticated for peace of mind, so please be aware of that. The size is based on how it felt to me, as I usually wear 27.5-28cm shoes. Although I haven't worn it much, there are some scuffs on the insole, so I will remove the insole before shipping.