VOLUME CONTROL: AM FM portable radio comes with 3.5mm plug stereo headphones for rich stereo sound. Volume control for accurate volume adjustment according to signal strength, meeting your various needs. STEREO SOUND: AM FM pocket radio has a built in compact but clear sound quality speaker with stereo headphone sound (headphones included), so you can enjoy stereo sound anytime and anywhere. RECHARGEABLE BATTERY: Pocket radio has a built in 500mAh rechargeable battery that can operate continuously for up to 10h on a full charge. The lock button is designed to prevent accidental operation when the radio is in your pocket. DIGITAL SIGNAL PROCESSING CHIP: Mini radio uses an excellent digital signal processing chip for more stable reception and better reception in weaker signal locations. Frequency range is FM 87108MHz, AM 5201710KHz. WIDE RANGE OF APPLICATIONS: Mini digital radio is great for walking, running, biking, gardening, traveling or other outdoor sports. Simply put on the headphones and enjoy your relaxation time.