Not much to say here, as you can probably get all the info you need from Amazon's photo.
The item is well made and works well with the base of the light fitting wedged into the bottle neck or vase opening.
Bew aware that the spines on the base stopper snap off easily, presumably this is a feature not a fault and in fact it is necessary to remove them the fit into a narrower bottle opening. Note also that the power cable feeds into the side of the bulb holder rather than through the base stopper - this is best for bottle lights but less elegant if it is to be used in a vase or base which has a bottom cable opening (as one of ours does).
Otherwise this is perfect for converting your wine bottle into a lamp.