AO Coolers are the best soft-sided coolers in the industry. do not be fooled by imitation coolers made to look like ours. AO Coolers are guaranteed to never leak or sweat because of a high quality liner, the same material used to make waterbeds and above ground pools. The inner insulation is three-quarters thick, high-density, closed cell foam. The combination creates a cooler that will hold ice for 24 hours in 120-degree heat. AO Coolers are guaranteed for life. If it ever leaks they will replace the liner.