Sears offers the DieHard 140-watt Power Inverter with USB, model no. 71522, for $19.99. Choose in-store pickup to dodge the $6.50 shipping charge. That's the best deal we could find by a buck; most stores charge $25 or more shipped. This fan-cooled adapter plugs into your car's DC outlet and provides power through a 110-volt household AC outlet and USB port.
Of note, Shop Your Way Rewards members will earn a Sears credit with this purchase and may be eligible for additional credits and discounts. Plus, Shop Your Way Max members are eligible for free shipping.