Sunward Pet Dog Collar,LED Pet Dog Night Safety Collar Dog Harness Large Dog Luminous Band,Adjustable Size S :Bust:40-48cm/15.7-19.0'', Width :2.0cm/0.78'' Size M :Bust:52-60cm/20.4-23.6'' ,Width :2.5cm/0.98'' Size L :Bust:58-76cm/22.8-29.9'' ,Width :2.5cm/0.98'' Rain resistant, durable and adjustable. 3 lighting modes: Constant on, strobe and Flashing(with switch to select)