Water bottle sling designed to carry Bestie Bottles. *The Bestie Sling is the cutest way to carry your Bestie Bottle wherever you go. *Made from flexible, durable silicone, these slings come with exchangable charms that let you express your unique style. *The strap adjusts easily for a comfortable, hands-free fit, making it your ultimate sidekick for strolls, adventures, and everything in between.