The thermos does not contain aluminum and BPA. The material used is stable, non-toxic and does not leak into the liquid. Thanks to the high-quality 18/8 stainless steel, this thermos just doesn't break. Even if it falls to the ground from a height, it will not squash and retain its function. The double wall and vacuum perfectly insulate and prevent heat transfer, so the ambient temperature does not affect the temperature of the liquid inside. Monkey Shield double-wall vacuum insulation technology ™ 18/8 stainless steel does not transmit a metallic odor. The optimal hole size eliminates splashes in the face and fits on standard ice cubes. It stays cold for 24 hours and hot for up to 12 hours