LED Light Up Dog Collar with Reflective strip. LED JEWEL LIGHTS With 3 Flash Modes: Solid, Blink Fast, Blink Slow Battery Life: 60 hrs run time continuously. Tip: For Longest Battery Life use "Blink Slow" mode. Adjustable Sizes: Extra Small 9in -12in, Small 11in-16in, Medium 13in-20in, Large 15in-24in, Extra Large 23in-32in LED Jewel Collar with Reflective Strip Perfect for Walking, Running, Hiking and Camping. Keeps your dog safe and visible at night. Water resistant and great for all conditions, light weight, durable. Easy to Replace Batteries and comfy around your dogs neck.