Different teas require different water temperatures. White and green teas are best brewed at 175 Degree F, while herbal should be steeped at a steaming 208 . Oolong prefers 195 , and black tea 200 . And don't forget about coffee! Pour-over, for example, requires 196 - 204 for perfection. With the Clarity Adjustable Temperature Kettle, you can select the precise temperature for your tea or coffee by simply twisting the knob. The crystal-clear, BPA-free borosilicate glass ensures a pure, clean taste that won't interfere with flavors and aromas. No matter your cup of tea, the Clarity Kettle provides a pure and enjoyable experience.