I used to dread a dead car battery because it meant flagging down a stranger or waiting an hour for roadside help. Then I left my headlights on one too many times and finally bought a portable jump starter. It has saved me four times on a single charge.

What it actually does

A portable jump starter is basically a power bank for your car. You clamp it to the battery, wait a second for the light to go green, and start the car like normal. No second vehicle, no jumper cables, no asking a stranger in a parking lot.

What I looked for

• Enough cranking amps for your engine size. Bigger engines need more.
• A built-in light, because dead batteries always seem to happen at night.
• USB ports so it doubles as a charger for your phone in an emergency.
• Safety features like reverse polarity protection, so you cannot fry it by hooking it up wrong.

The first time I used it, I was skeptical it would work. I clamped it on, turned the key, and the engine fired right up. I have jumped my own car, a neighbor’s truck, and a coworker’s sedan with it, all before needing to recharge.

The only catch is remembering to top it up every few months, because a dead jump starter is useless when you need it. I set a calendar reminder and moved on with my life.