The Nite Ize PetLit LED Collar Light is a unique battery-powered LED that you can clip securely to your pet's collar, keeping him or her stylish and visible at all hours of the day and night. Made of durable plastic with a playful design or jewel crystal decoration, the bright LED light is easy to activate with a simple twist. It's a fun, yet reliable way to keep your furry friend safe and visible when you're out hiking, camping, running, walking, or playing in the park - and all other early morning or late evening romps. Compact, convenient illumination Battery Run time: 24 Hours Easily replaceable 1 x 927 3V lithium battery included Weather resistant Secure clip - easy to attach and remove from the D-Ring of a pet's collar Twist on/off Dimensions: 1.73" x 0.97" x 0.62" | 44.02mm x 24.82mm x 15.87mm Weight: 0.18oz | 5.00g