LED Flashing Pet Collar Glowing Dog Collar Safety Walking Pet USB Rechargeable And Adjustable. Fashionable, they combine the functionality of illuminated LED lighting with awesome looking patterns. Allow you and others to easily spot your pet from a distance when it is dark outside, and look great during the day! You can easily see where your pet is at all times. Combining a lighted collar and lighted LED leash is the perfect way to keep your pet visible to you, other people and car driver at night or times of low visibility S : 13.38-16.14 in M: 14.56-18.11 in L : 16.14-20.47 in XL:16.53-22.04 in Product Component: Polyester, optical Fiber Strip+Plastic Buckle+ Metal D-ring etc. Luminous Modes: Each product has both quick flashing, slow flashing and stable bright three modes available. USB rechargeable battery pack(matching USB cable included), the full charging time is about 2 hours, the working time is 2-3 hours