I understand that to mean that it's had only 10 full charges.. so it's almost unused... You can ask the seller to take a photo of the battery data to prove it's true if you want...
But I'd be wary - All batteries are 'genuine' (ie: they are truly batteries) but is this a battery 'genuinely' MADE by DJI? It seems a bit cheap, if so... However, DJI contracted out battery manufacture anyway, so it all gets a bit complicated.
However, although I have 2 genuine (as in 'made by DJI') batteries, if I wanted to buy another, then I would be willing to take a risk on that deal, even if it turned out to be non-Original Equipment Manufacture (non-OEM) on receipt... It might still be OK, nonetheless...
(Later) Seems to be the same as this one but your pic covered up the 'USA Stock bit'...That's just a generic picture, I think. However, it seems to be posted from Bexleyheath, Kent, UK and delivered within 5 days...
My prediction (from a lot of experience of buying such Ebay.co.uk things) is that it will probably be posted quickly and arrive on time. It won't be a genuine DJI battery but it WILL be a battery which fits a P3 and it might work OK. However, the link I found (is yours the same or says 'unbranded'?) states the manufacturer as 'DJI'. If you find it isn't genuine DJI when you get it and it isn't new (as also stated), then send it back and claim a refund, but you have to pay the postage. If no refund from the seller, then raise a case with Ebay for a refund.
The choice is yours...
Genuine Battery for DJI Phantom 3 Professional Advanced Standard 10 charges. Condition is New. Dispatched with Royal Mail 1st Class.
www.ebay.co.uk