TomTop offers this Portable 10-watt Monocrystalline Silicon Solar Panel USB Charger for $11.29. Coupon code "SOLA33CX" drops it to $7.99. With free shipping, that's the lowest price we could find by $5. It measures 10.2" x 5.5" x 0.08" and features a USB charging port, carry handle, and four suction cup mounts.

Note: This item ships from China and requires 10 to 20 business days for delivery. The countdown timer on the product page does not reflect an actual expiration time and resets daily.