Warm days call for frozen cocktails which calls for these cups. Because slushies aren't fun when they're melted. These margarita cups will keep cold cocktails (and refills) nice and frosty. The cups are double-walled BPA-free plastic with a unique gel inside. Once frozen, the gel keeps drinks at 43°-53° F. And while the cups are chilly, your fingers won’t be. A silicone band makes the cups comfortable to hold. For best results, freeze cups upside down for 2 hours or more. Hand wash only.