Lifeventure thermal mug jacket 185x85x85mm product description designed to protect your thermal mug this jacket will also improve the thermal properties of your mug by adding another layer of insulation tests have shown an increase in heat retention of up to 25 percent the thermal mug jacket is made from tough cordura fabric and features soft inner lining with foam padding for maximum durability and protection features protects and insulates your lifeventure thermal mug impro