As the rest of the NYC nail line, this product can be picked up for around $1.50. It is a super-glossy topcoat used over any nailcolor and is supposed to add shine and longevity to polish. It most definitely adds shine, which is why I continue to use it. However, it doesn't seem to help the life of the underlying polish. It tends to peel away if hastily applied.
If you're looking for an ultra-high shine finish on your nails for a special event, this is probably the way to go. Otherwise, look elsewhere.