OPI Nail Envy - Bubble Bath Like many of our other nail strengtheners, Nail Envy Samoan Sand provides maximum strengthening aid to transform weak, brittle, damaged nails into stronger, longer, harder nails shining with bold, true-to-bottle color. This iconic product is a holy grail treatment for many, but what even the biggest OPI fanatics don’t realize is that this nail strengthener comes in more unique formulas designed to target your most annoying nail conditions.