The Hydro Flask 12oz / 355mL Kids Wide Mouth Flask - Firefly keeps every sip icy cold for up to 24 hours. When playtime wraps up, the perfect refreshment is waiting. With a colorful, easy-to-clean Straw Cap and a durable perforated Flex Boot, the Wide Mouth Kids Bottle is the perfect companion for any adventure. The straw lid is not leakprook and is not intended for use with hot liquids.