Who just became the most popular person at the campfire? You did. When you started passing the Highline Whiskey Flask around. You know the drill...sip, pass, repeat. The Highline puts 9 ounces worth of party in your pocket. Made from durable stainless steel and coated with our DuraGrip finish, this flask stands up to the shenanigans that are sure to ensure. High-Grade 18/8 (304) Stainless Steel - highly durable and corrosion-resistant. BPA Free Never Lose Cap DuraGrip Powder Coat Finish - our proprietary finish is both ultra-durable and provides a textured surface for a sure grip.