Colorful protection. Make your Hydro Flask your own with a colorful, durable silicone Flex Boot. Customize your look and protect against bumps and dings. Small boot fits 12-24 oz wide and standard mouth bottles. if your bottle is bigger than 24 oz, check out the Medium Flex Boot here!  Product Benefits: - Removable, silicone boot adds extra protection to your Hydro Flask - Small boot fits 12-24 oz wide and standard mouth bottles - BPA-Free - Lifetime Warranty