High-Temperature Resistant Glass, stainless steel infuser and cap, and nylon sleeve.
 
Add tea and/or herbs to the infusing basket and then add water.  It's as simple as that to have hot or cold tea with you where ever you are! The sleeve will help maintain the temperature of your drink for hours. 
 
Sleeves are Black, Navy Blue, Pink, Gray, and Green.  Please indicate which color you want in the comment section when submitting your order.