Performance with Style - The BOULDER is our flagship bottle, now in a NEW 32 oz Size. Featuring our TriMaxà triple insulation technology, this bottle is vacuum insulated and tested to keep liquids cold for 36 hours and hot for up to 8 hours. You can fill this bottle with both cold and hot drinks and take it anywhere, since its secure top will keep your drink inside where it belongs. So, toss it in a tote bag or backpack and hit the trails, golf course, run errands around town or keep on your desk for convenient hydration through the day.