JBL Flip 4 Waterproof Portable Bluetooth Speaker (Black) (Certified Refurbished) Wirelessly connect up to 2 smartphones or tablets to the speaker and take turns playing impressive stereo sound Built-in 3000mAh rechargeable li-ion battery Supports up to 12 hours of playtime Ipx7 waterproof means no more worrying about rain or spills; you can even submerge flip 4 in water Ubl connect+ allows you to Link more than 100 JBL connect+ enabled speakers together to amplify the party