OPI Nail Envy, $15
A few coats either by itself or underneath polish will help to make sure your nails stay strong by reinforcing the natural nail. If you're trying to grow your nails, this is your new best friend.
Sally Hansen Advanced Hard As Nails, $10
Extra-strength strengthening treatment that hardens nails and smoothes ridges, formulated with nylon, retinol, soy and omega 3 to fortify nails for a hard, healthy-looking shine that lasts.
Revitanail Nail Strengthener, $19.99
A multi-award-winning nail care treatment to promote stronger, longer and healthier looking nails.
MAVALA SCIENTIFIQUE Penetrating Nail Hardener, $19.95
By quickly hardening the nail, MAVALA SCIENTIFIQUE allows soft, flaking or splitting nails to become healthy and strong. Its formula hardens the nail plate and restores the nail normal growth.