This listing is for a B&O (Bang and Olufsen) Beoplay S3. It can be connected either via Bluetooth or 3.5mm mini-jack or Micro-USB wired connection. Some more information:
The Beoplay S3 is equipped with a dedicated 4-inch woofer (base unit) alongside a 3/4-inch tweeter, providing surprisingly deep, rich, and controlled bass for its small size. It uses two 35-watt Class D amplifiers to deliver high-quality sound with a balanced, non-muddy, and punchy bass experience