How to Choose a Vacuum Flask: Steel, Seal and Insulation
Material grades, lid mechanisms and insulation benchmarks explained for wholesale buyers.
Key takeaways
- 304 (18/8) stainless is the food-safe baseline; 316 suits acidic drinks.
- Vacuum layer quality decides hot-hold time: expect 6-12h for good bottles.
Sources
Manufacturer spec sheets; GB 4806.9 food contact standard.