Regarding the battery, it is difficult to give an opinion with so little setback but we can say that the assembly was rapid (this remains a battery, so in terms of difficulty a child could handle). I personally did not charge the battery before using it and it did not prevent it from starting clockwork.
When the price do not talk about: 81 Amazon or anywhere else on the net, 165 at retailers like Feu Vert, Norauto & Co. There is no picture.
So ... Seller more effective, product line with what I expected! Go for it!
