1. Longlasting playback with builtin battery 2000mAh rechargeable lithium battery provides extended music playback on a single charge. Designed for reliable, continuous use without frequent recharging. 2. Portable and easy to use Cardsized, compact design easily fits in pockets or backpacks. Tactile, wellplaced physical buttons enable blind or feelbased operation to switch songs or modes. 3. Lockable buttons to prevent accidental changes Button lock feature keeps your settings intact during travel or storage. Use the HOLD switch to ON to lock all buttons and prevent unintended touches. 4. Thoughtful design for all ages Suitable for a wide range of users, including children's English listening practice and seniors who enjoy opera or other audio content. A versatile listening device that adapts to everyday needs. Use scenarios On the move: for commuting, travel, or gym sessions where you want uninterrupted playback and secure controls in a compact package. Language practice and learning: Ideal for children practicing English listening skills or users following language programs, with easy tactile controls. Relaxed listening for seniors: Simple operation and a reliable lock feature help provide a comfortable listening experience during leisure time, without worry about accidental button presses.