When it comes to less lethal self defense tools, several come to mind including pepper spray and tasers. Neither is designed to end an encounter but rather to temporarily incapacitate the attacker so the defender can retreat to a safe location. Whether you use pepper spray or a taser as a less lethal self defense tool is up to you. Your Wisconsin CCW permit allows you to carry a taser concealed in addition to or instead of your handgun.
Many stores both online and brick and mortar sell tiny, hand-held devices they call tasers. The problem with these is that the defender has to be within arms-reach of the attacker and at that range it’s very easy for the attacker to prevent the defender from grabbing anything.