It seems you can cool down a single serving of freshly brewed coffee, tea, or other beverages in about 7 minutes. It's good that it doesn't dilute the drink because you don't use ice. You need to freeze the inner bottle beforehand. If you put a cold drink in it instead, it might become a slushy drink perfect for summer. Please try it if you purchase it. Please consider purchasing it before the hot season arrives. Please note that we do not plan to lower the price further, considering the shipping costs.