【NIGHT SAFETY GUIDE】Are you worried about losing your dog when walking at night? Our luminous dog collar will help you eliminate these problems. Our ultra-bright dog collar is very bright and easy to see, allowing you to maintain 500 meters of visibility in low light or no light conditions, allowing distant drivers, cyclists and joggers to see you in advance at night. 【HIGH QUALITY MATERIAL】This dog collar is made of nylon and PU leather, which is durable and waterproof. This flashing dog collar is slightly waterproof, don't worry about walking your dog in light rain every day, but don't let the collar get soaked in the rain or wash the collar for a long time, wipe it gently to ensure that it works normally. (Note: Please do not wash and soak in water). 【FULLY USB RECHARGEABLE】This personalized dog collar is USB rechargeable (charging cable included), more economical and environmentally friendly. 【DUAL-USE COLLAR - MULTIPLE COLORS】Our dog collar is designed with a unique dog paw print, which is stylish and ideal for glowing in the dark for added safety. This luminous dog collar has a six-color adjustable constant light mode (red, blue, green, pink, light blue, yellow) and a 6-color automatic cycling light mode, and a one-button power switch, allowing you to quickly find your pet. 【3 Adjustable Sizes】Our dog collar comes in 3 sizes. Please make sure to measure your dog's neck before ordering, do not just choose one size based on your dog's weight or breed. Size S fits neck circumference 30-40 cm (11.8-15.7 inches); M: 40-50 cm (15.7-19.7 inches); L: 50-60 cm (19.7-23.6 inches). (NOTE: Adjustments are not limited to the black nylon adjustment area)