Rivers & Mountains 18oz Steel Bottle

HOW IT WORKS

Here's how it works: the space between the inner and outer flask wall is evacuated, creating a vacuum (well, a partial vacuum anyway...). In order for heat transfer to take place from the outside world into your cold drink, or from your hot drink to the outside world, it needs nearby molecules to excite. If there aren't many molecules nearby, as is the case in a vacuum, the heat's energy can't easily be passed along, so your drink stays close to the temperature it was when you put it into the flask for a really long time. 

Simply stated, vacuums make great thermal insulation!

MATERIALS / SPECIFICATIONS

• Width	2.75"
  Height	8.27"
  Opening	Wide mouth
  Features	Compatible with most 18oz flasks
  Material	High-grade stainless steel, Lead-free
  Origin	Designed in Oregon, Built responsibly overseas
  Cap Material	High-grade stainless steel
  Care	Hand wash only