18-8 dual wall Stainless Steel with Copper-lined deep draw liner Vacuum insulation provides 11X heat retention Lead-free vacuum seal Leak-proof screw-on lid with visual open/close push button locking closure Lip groove allows for drinking spout to be positioned without even looking Lid can come apart for easy cleaning Black powder-coated body with silicone band accent Silicone band accent available in 15 different colors Patented