As a base coat , it prevents yellowing and staining of nails and also serves as a primer for applying colored nail polishes. It can be used alone or in conjunction with other nail polishes. As a top coat, it makes the colors on your nails last longer and be brighter for a perfect manicure effect that lasts longer. It is recommended to use it in both ways: - Base: apply a coat before nail polish. - Top coat: apply a coat after the nail polish to extend its duration.