A fun and functional way to keep pets visible at night. Set in a stainless steel carabiner, it easily secures to collars, harnesses and leashes. With and easy push on/off button, the Disc-O select has six selectable colors and Disc-O color changing mode. The long-lasting LED light has a battery run time of 20 hours, and the batteries are easily replaceable with 2 x 2016 3V lithium batteries (batteries included). Weather resistant.