It is typically made of food-grade 304 stainless steel, which is rustproof and durable.
The flask features double-wall vacuum insulation for effective temperature retention.
It often comes with multiple internal layers or containers to separate different foods.
Capacities can range from around 1.2 liters to 2.5 liters or more.
Key features include a wide mouth for easy filling and cleaning, a portable handle, and a leak-proof design.