This Thermal Insulated Water Bottle is Made with Inner 304 Stainless Steel Metal & Outer 201 Stainless Steel Metal, Featuring a Water Expanded Inner Liner for Enhanced Durability & Thermal Retention. the Double Wall Construction Helps Maintain Hot or Cold Temperatures for Extended Use. Designed with a Secure Flip Top Lid & Integrated Drink Spout, It Allows Easy One Hand Operation During Travel, Sports, School, or Outdoor Activities. the Ergonomic Shape Provides a Comfortable Grip & Fits Most Cup Holders, While the Smooth Exterior Supports Logo Display for Branding.