Brent- that is an e-collar. I like to use one on the belly strictly for "whoa" and steadiness. I do this to eliminate confusion since a stimulation on the neck could mean a multitude of different things. (Whoa, come, leave it, etc..) A dog's natural instinct when stimulated on the belly is to raise up their back end and essentially stop. Therefore, when they feel that zing on the belly, they know exactly what that means and there's no question. I now have control of that dog when they are out say 200 yards. I can correct on an honoring situation, a bird flushing, or maybe even before they cross the road with oncoming traffic when they need to stop. Very powerful tool when applied correctly. (These are all pictures I took during training so she has the belly collar on.)