Amazon.com has Skullcandy Barricade Bluetooth Wireless Portable Speaker, Black on sale for $18
https://www.amazon.com/gp/product/B01DWHPUVQ/
- Delivers seamless integration with any Bluetooth-enabled device
- Skip the cord and listen Longer with up to 8 hours of rechargeable battery life
- A 10W speaker and dual passive radiators work in concert to create powerful, dynamic sound with impressive low end bass
- A rugged design that’s impact resistant, buoyant, and IPX7 waterproof up to 3-feet Underwater
- Connect multiple speakers for music as loud as you like