This tool is incredibly effective. ive zapped myself with it to test. feels like a very very strong static shock. Our dog Solo has been zapped only a handful of times. When he wears the collar now we don't even really turn it on or use it - just knowing it exists is enough for him to drop his frisbee/ball/etc. https://www.ecollar.com/product/ez-900-easy-educator-1-2-mil...