Mercedes used cars for sale in Berkshire? Autovehicle buying news: The STANLEY J5C09 is one of the bigger ended, but still among the best portable jump starters on the list, weighing 18 pounds and measuring 11.2 x 8 x 13.5 inches. However, if you’re driving a larger or heavier car, it’s the portable jump starter for you. It offers 500 instant starting amps with a peak of 1,000. It also includes a 120-PSI air compressor, so you can fill up your inflated tires, and a USB port, so you can charge up your mobile devices. If you happen to be …