The ideal gift! Buy the best ready-to-drink online. Price and reviews available for Canteen Canteen Grapefruit Vodka Soda Ready-to-drink – 6x 12oz Cans. Sweet, sour, tart, and tangy. Our Grapefruit takes Mother Natures most deliciously conflicted flavor and creates a concoction thats never confused when it comes to refreshment. Contains only 99 Calories and NO Sugars, Carbs, or Sodium. Gluten Free.