The Yellow Jacket is a case for cell phones that is actually a 650,000-volt stun gun. It has a safety switch and cover for the electrodes to prevent an accidental discharge.
There is an external battery capable of powering a smart phone for 20 hours.
The inventor came up with the idea after surviving a home invasion.
His company is still raising money to fund production, but it is taking orders. The Yellow Jacket is selling online for $125.