Nubeestore via Amazon offers the Volmate 3.4-amp Dual USB Car Charger in five colors (Black pictured) for $12.98. Coupon code "VOLL7OFF" cuts it to $5.98. Plus, Prime members bag free shipping. (Non-members can spend $35 or more for free shipping; otherwise, shipping adds $5.13.) That's a $7 savings and the lowest total price we could find. This MFI-certified charger features 2.4A and 1A USB ports for a combined 3.4A. It's compatible with most smartphones, tablets, and other USB-charged devices.

Also available is the Volmate 4.8-amp Dual USB Car Charger in five colors for $14.98. Coupon code "VOLH8OFF" cuts it to $7.25. Plus, Prime members bag free shipping. That's an $8 savings and also the lowest total price we could find. It features two 2.4A USB ports.