This portable bottle warmer is made of non-toxic and durable material which is safe for mummies and babies. It is wrinkle resistant and retains shape well. Say no to scrambling to find hot water! -->Good Insulation: Can hold standard size bottle x 2, wide bore bottle x 1. It can warm up your breast milk before feeding baby on the go. It is easy to clean and maintain too. -->USB Heating: Come with USB cable, just connect the cable into any power bank, vehicle USB or laptop interface. The additional pocket of our bottle warmer can accommodate a power bank for travel convenience! *Portable power bank not included.