Make your larger 32-40 oz Iron Flask water bottle even more dependable with this stylish, BPA-free silicone protective boot. With its snug, seamless fit, this insulated sleeve adds another layer of protection to the double-walled insulation of your Iron Flask water bottle, while keeping it scratch and dent-free. This soft and flexible sleeve is available in a range of colors, so it’s easy to match with your gear and ‘fit.