We partnered with Miir to offer a water bottle that stands up to the same abuse as our bags and apparel. Built to endure.Constructed from 18/8 Medical Grade Stainless steel, this 32oz bottle is guaranteed to be water tight. The Howler bottle keeps contents cold for 24+ hours and hot for up to 12 hours.Thermo 3D (TM) Double Wall Vacuum Insulation Technology Content stays cold for 24+ hours Content hot for up to 12 hours BPA free Threadless lid seals carbonationdoesn't leak 18/8 Medical grade stainless steel Powder Coated