SKU: BT-155E-RD Smartphone Speakerphone: If you have a Bluetooth-compatible phone, you can pair them both to play your music files wirelessly, or stream from your favorite apps. When paired with a smartphone, you can use the built-in mic to transform the BT-155E into a speakerphone for hands-free calling. Built-In Controls-On the top of the BT-155E are tactile, rubberized buttons that let you manually controls the speaker. You can use them to switch to hands-free calling, play and pause music, pair it with a Bluetooth-compatible device, power it on and off, and adjust the volume.