Material: Polyester webbing, fish screen light-transmitting surface, light-guiding flat optical fiber (length can be cut freely)Flashing mode: long light, fast flash, slow flash (controlled by switch), colorful colors progressively.Colour: BlackPacking: 1pcs Battery life: 30-40 hours, about 2 months of normal use; about 30 hours in the constant light state, the battery can be replaced by yourself, and it is available in convenience stores or supermarkets. Clean removable electronics. The charging model can be charged for about 30 minutes and can be used for two hours. This product is suitable for walking the dog in a dark environment or at night, outdoors and pet sports, it emits light through optical fiber, which acts as a warning, and can be used by pets when the light-emitting function is turned on and off during the day or at night [Specification]: Size S: Suitable for neck circumference 34-41cm, width 2.5cm, overall length 44cm, weight 50g, use 2 pieces of CR2032 batteries Size M: Suitable for neck circumference 37-46cm, width 2.5cm, overall length 50cm, weight 56g, use 2 pieces of CR2032 batteries Size L: Suitable for neck circumference 41-52cm, width 2.5cm, overall length 56cm, weight 58g, use 2 pieces of CR2032 batteries [Reminder] Choose the size according to the actual neck circumference of your dog! Between different colors: the brightness of yellow and orange is high. [Function introduction]: Each model has a hidden switch, with 4 functions: fast flashing, slow flashing, static flashing, off. Comes with a button battery (remember to take off the collar when taking a shower, just pull out the battery box), button batteries are very convenient to buy in supermarkets! [Picture and description]: A light in the dark! Fashion luminous collar, no longer have to worry about not being able to find the dog, safe travel at night, personality, fashion