Yoo YX2500RS 1 Shoe Clip Activty Tracker (Raspberry) Easy-to-use wireless activity tracker Track daily steps, distance and calories-burned LEDs light up to track progress Wave the LEDs in the air to display step count instantly Clips on to a shoe or belt loop or slip into a pocket or bra Easy-to-use Wireless Activity Tracker Track Daily Steps, Distance & Calories-burned Slip On To A Shoe Or Belt Loop Or Slip Into A Pocket Or Bra Water-resistant 1+ Year Battery Life