Our personalized flasks feature a double wall construction. This technological breakthrough can keep your hot drinks hot or your cold drinks cold! Perfect for use at the gym, hiking outdoors, working in the field, college, or commuting! We use state-of-the-art laser engraving machines to ensure the clearest, high-definition finish on your bottles that will never rub off or fade! Crafted from high-grade stainless steel, this premium bottle is generously sized and available in 500ml and 750ml sizes, ensuring your drink stays piping hot for up to 12 hours and refreshingly cool for 24 hours. Optimum temperature maintenance is guaranteed, ensuring your drinks are always enjoyed at their freshest, whatever the weather.