The flask will prolong the using time if you follow a few simple guidelines:

1.Rinse the inside with clean, soapy water before filling the flask for the first time.

2.Always empty the flask after use and rinse thoroughly before refilling.

3.Please avoid pouring the powerful alcohol into the flask.

4.Please avoid using the flask at high temperature.

5.Please don't keep alcohol in the flask longer than a period of 3 days. Refill only when you are about to use the flask.