Promate 2000A/12V Heavy Duty Car Jump Starter with Power Bank / 2000A/12V Heavy Duty Car Jump Starter with Power Bank / 20000mAh Battery Capacity / 45W PD USB-C Input/Ouput port / 2 x 18W QC 3.0 Ports / 280lm LED Torch / Smart Clamps / LCD Screen / SPARKTANK-20 / SPARKTANK-20

The Promate SPARKTANK-20 is a 12V jump starter with a 2000A peak current and a 20,000mAh battery that doubles as a power bank. One device therefore covers a flat car battery on a Monday morning and a flat laptop on a long drive, which is why it lives in a boot rather than in a garage.

The jump starter delivers a 1000A starting current held for one second and a 2000A peak for 0.2 seconds, on a 12V system. Promate rates that as strong enough for cars and motorcycles, and the short high-current burst is exactly what a starter motor needs to turn an engine that will not crank.

The supplied smart clamps protect against current overflow, short circuits and reverse polarity. That last one is the common failure: connecting the wrong clamp to the wrong terminal at night, in a hurry, when a car has stopped somewhere inconvenient. The clamps catch it rather than passing the fault through.

The internal pack is rated at 20,000mAh, or 74Wh, which is enough for multiple jump-starts and device charging from a single fill. Capacity is what determines whether the unit is still useful after the first emergency, and this rating leaves headroom rather than being spent on one crank.

The USB-C port works as a 45W input, accepting 5V, 9V, 12V and 15V at 3A and 20V at 2.25A. A 74Wh pack refilled at 45W is back in service far sooner than one crawling in over a 5V charger, which matters for a device whose whole purpose is being ready when you need it.

The same USB-C port also outputs 45W, stepping through 5V, 9V, 12V and 15V at 3A and 20V at 2.25A, which is enough to run a laptop or tablet at speed. A separate DC output supplies 15V at 10A for accessories that expect a vehicle-style supply rather than USB.

Two USB ports support Quick Charge 3.0 at 18W each, so two phones can charge quickly at once without either being throttled. On a road trip that is usually the more-used feature of the whole unit, since the jump starter sits idle while the passengers' devices do not.

An 8W LED torch rated at 280 lumens runs in solid, SOS and flash modes, and a smart screen indicator reports the remaining power level at a glance. The build is compact but rugged, made to survive being thrown in a boot and to work in the conditions where you would need it.