The 650ml Thermal Vacuum Insulated Flask features a 304 stainless steel construction, making it both durable and heat-resistant. Its large capacity, food-grade materials, and sealed lid provide safe and healthy storage for drinks, maintaining temperature for up to 6-12 hours. The leak-proof design and anti-slip bottom add convenience and stability, while the portable belt style adds a touch of fashion for easy carrying. It's the perfect choice for outdoor sports and activities.