PetSafe SportDOG Brand Locator Beacons - Bright, Waterproof Dog Collar Light with Carabiner - Flashing or Solid Safety Light Highly visible, long range dog collar light can be set to ON or BLINKING to make your dog visible at night or in low light senarios for silent tracking; Included carabiner allows for easy attachment to a dog collar D-Ring, a backpack strap, a belt loop, and many other places, or easily slip it on a 3/4" or 1" collar strap All-weather safety light features waterproof and submersible design ensuring reliable use during rain or when your dog goes swimming Available in blue, green, red, white, and yellow; Pick your favorite color, select a different color for each dog, or select multiple colors for 1 dog, using 1 color for the dog's right side and another for the left side, allowing you to easily determine what direction your dog is headed Replaceable CR2032 batteries provide up to 250 hours of on time; Setting the light to flashing provides longest battery life