Whether you're just looking to extend the life of your at-home mani by a few days, or trying to quit your $45/month salon habit cold-turkey, a top-coat polish will help you out. But instead of gazing mindlessly at the polish wall at Target, plucking the first colorless bottle you see, take a cue from those who know best. We talked to a few trusted nail pros, who gave us their favorite top-coat polishes and told us why each one is clear, liquid gold. Ahead, find your new nail topper — and a welcome three weeks before your next mani/pedi.