Additional dog training collar to suit Dogtra Edge remote dog trainer. The collar is fully waterproof and rechargeable. It comes with 4 different collar coded collar strap to be matched with the color coded button on Dogtra Edge remote trainer transmitter. The built in light indicator can be set into 4 different color to be matched with the collar strap as well. Please choose the right collar for your system. Normally the system comes with the Black color collar, the second collar should be Orange, the third collar is Green and last collar is Blue.