KRight Rechargeable Led Running Belt Reflective Flashing Polyester Led Belt Bicycle Jogging Party Reflective Belt LED Light Strap Decoration Party (Blue) LED light-emitting optical fiber strap PU super bright light guide fiber + ABS engineering plastic switch box By switching regulator Long bright. Flash. Slow flashClose Emitting fiber length 280cm, diameter 0.28cm, elastic band length 100cm, width 3.8cm Product itself comes with the original button batteries, 4 (original as CR2032), long light emission time of the measured data for sustainable 80 hours; battery can replace