Click to expand Tap to zoom OPI Nail Envy Nail Strengthener Original Formula by OPI Sold out $18.00 | / 1 2 3 4 5 6 7 8 9 10+ Quantity Quantity Sold out Nail Envy Nail Strengthener Original Formula By OPI Helps Nails Grow Harder, Longer, And Stronger, And Resist Peeling, Cracking, And Splitting.