leaflife premium bamboo thermos with tea infuser & strainer- 17oz capacity- keeps hot & cold for 12 hrs- vacuum insulated stainless steel travel tea mug- infuser bottle for loose leaf tea & coffee leaflife for hot or cold drinks coffee. ice tea. fruit infused tea. our tumblers are designed to hold any beverage and keep it hot for 12 hours or cold for up to 24 hours. this is due to our vacuum insulated design where we take no prisoners (except for heat). where heat is trapped in the tumbler due to the vacuum to ensure that your breakfast coffee stays piping hot. the vacuum works both ways, and prevents the heat outside from warming your fresh ice teas too! our tumblers are made from quality materials, featuring 18/8 food grade stainless steel inside and a fine bamboo coating on the surface.