Soondar&reg; Outdoor Sport Watch Speaker, Band Speaker, Built In Microphone, Built-in Rechargeable Battery, Support Micro-SD Card, FM Function, Your Best Friend for Sports Running Easily to switch music playing mode to phone calls mode wireless technology. Built-in microphone supports hands-free calling Suitable for running, cycling, dancing, and other light exercise Support Micro SD Card, Compatible with MP3 format Let the music to accompany you anywhere