Poly Extension Nail Gel Set 15ml 12 Colors White Clear Crystal UV Builder GelOverview Poly Extension Nail Gel was inspired by a desire to create a product that keeps everything nail techs like about acrylic and hard gel systems while removing the aspects they don't like. Poly Extension Nail Gel is more flexible than acrylic, stronger than hard gel, and lighter than both. Unlike hard gel, Poly Extension Nail Gel is not self leveling, but stays where you place it; unlike acrylic, it doesn't harden until it's cured in an LED or