Replaceable CR2032: The dog collar lights for the dark comes with CR 2032 "button" Easily replaceable for long term use. Glow collar for dogs can keep going for 30 hours. It is the perfect addition to any collar, rope, leash, harness, or strap. IP65 Waterproof& Durable:Under the protection of the IP65 Waterproof, no matter rain, snow or sand dust, the dog camping accessories can not be affected in any way.The light up dog collars accessory is sturdy and durable, and the clip-on hook design is very convenient for installation and removal. Multi-purpose: Not just for your pets, the clip-on LED dog collar light can be clipped to accessories, backpacks, bikes, camping tents to improve visibility and keep you safe when you are walking, running, cycling and camping at night. 3 Highly Visible Light Modes:There are 3 modes light of the light up dog lights for night walking - Fast Glowing, Slow Glowing, Steady Glowing. Just press the on/off button to choose the modes that you need. And the dog tag is high visible up to 1/2 a mile away. LED Dog Collar Light: Our LED lights dog collar light are designed to keep your puppy safe while walking at night. The dog tag will allow drivers, cyclists, joggers & others to easily see your puppy from far distances. You can also see your dog better at the dark night.