Premium 12oz/16oz (350ml/500ml) double-walled vacuum flask with precision-crafted small mouth opening

High-grade 18/8 stainless steel construction with military-grade oxidation resistance and sweat-proof coating

Ergonomic handle design features reinforced welding points and non-slip silicone grip for secure carrying

Advanced copper vapor deposition technology between walls achieves 12-hour hot/24-hour cold retention

Mirror-polished interior resists flavor retention and passes FDA food-contact standards

Dual-purpose design transitions seamlessly from gym hydration to office coffee storage

Laser-engraved measurement markings with scratch-resistant coating for long-term visibility

Thread-free press-on lid with medical-grade silicone seal prevents leaks in backpacks or gym bags

Sandblasted matte exterior resists fingerprints and maintains professional appearance in corporate settings

Weight-balanced base prevents tipping during car commutes or outdoor activities