1. Keep the flask dry when not in use for an extended period.
2. To prevent odors and stains, clean the flask thoroughly and allow it to dry after use.
3. Using impure water may leave red spots resembling rust; these can be removed by soaking the flask in warm water mixed with diluted vinegar for 30 minutes, followed by washing.
4. Wipe the surface with a soft cloth or damp sponge moistened with a neutral detergent; the product must be cleaned thoroughly after every use.
