It is a double-layer vacuum insulated travel mug made of excellent insulation materials, which can keep hot and cold liquids (water, coffee, tea etc). Reusable, unbreakable and easy to wash; the inside of the lid is embedded with PP leak-proof silicone ring. You can use it in for sports, go to work, go to beach, school, office, picnic, hiking, camping, road trips, traveling, trip, driving, mountaineering, backpacking, hot yoga, gym, fitness. It is the best gift for friends, family, children, sons and daughters.