Ultimate Ears Wonderboom SE Wireless Bluetooth Speaker

Highlights
Wireless Bluetooth with a 40 meter (131 Ft) range
14 hours of boom on a single charge
Connect up to two source devices at the same time.
Water and Dustproof IP67 : can be immersed in water up to 1 m for up to 30 min
Maximum sound level: 86 dBC (normal) and 87dBC (outdoor)