Men’s Journal aims to feature only the best products and services. If you buy something via one of our links, we may earn a commission. Cold weather is notorious for killing car batteries, which means having to be extra prepared with a snow brush , a portable tire inflator , and even stashing an extra warm jacket in the back seat in case you get stuck. But the one tool you should never leave home without is a portable car jump starter like this bestseller from Walmart , and ...
