Simply fill the strainer with tea leaves and add boiling water. The clear pot lets you see the tea as it steeps, allowing you to determine the perfect strength. When the tea is to your taste slowly depress the plunger to stop brewing. No mess and no need to remove the strainer before you pour. Of course it works great for coffe too. 27-ounce Double wall borosilicate glass helps to retain the heat. The borosilicate glass is resistent to thermal shock and can handle extreme heat and cold temperatures. Borosilicate glass is also stronger than typical glass products. Stainless steel lid and plunger.