It keeps hot stuff hot and cold stuff cold, how does it know?

This Polar Camel tumbler is perfectly-sized for people on the go (20oz). It also features a clear push-on plastic lid with a narrow mouth opening to reduce the risk of spilling.

.: Material: durable premium stainless steel
.: One size: 20oz (0.6l)
.: Easy sipping, clear push-on plastic lid
.: Narrow mouth opening
.: 17 colors to choose from
.: Stipple print texture with possible white edges
.: NB! Full bleed designs suggested only on the silver color to avoid any unprinted gaps from the print and the silver ring
.: NB! Hand wash only