Shop Klean Kanteen 12oz Kanteen Wide Insulated w/ Loop Cap. Compact and efficient, the 12oz Wide Vacuum Insulated Kanteen keeps contents hot up to 6 hours, and iced up to 24. With a double-wall, all-stainless interior and no liner, flavors don`t linger and cleaning is a cinch. The leakproof Stainless Loop Cap gives you peace of mind if you want to toss it in a bag or lunch box. Adding a Café Cap converts this bottle into an awesome to-go mug.