Roypow J12 Portable Car Jump Starte, Emergency Battery Booster Pack for Gasoline 4L, Diesel 3L

This is a great bit of kit. I have an ageing estate car which I use rarely. As a result the battery dies. This small device jump starts it back to life with no problems. The Roy Power easy to charge, use and can charge other devices. It also features a torch. One word of caution; it can lose its own power over a period of time so it's as well to top it up every few months.

Will happily start even a big diesel engine, had to use it a few times due to dodgy car battery, started the car first time every time. Amazing when you consider how small it is and the fact it can be charged using a USB cable!

Excellent works as expected well packaged nice case.

What a useful piece of kit, I have had to use it twice to start my diesel car when the battery was dead and its turned the engine over as sweet as a nut. I am really impressed.

Did nothing for my 2.4L diesel engine. Barely lit up the dashboard when ignition key was turned

This is a well made gadget that is easy to use and has a number of uses. I bought it to jump start my car battery and was pleased with how simple it was to charge up and fix on. It is also small so can balance easily when you have the bonnet open. The instructions are clear and I like the fact it has a bright colour.

Great could be a life saver

Did nothing for my 3L diesel. Returned the item after multiple attempts and finally giving up.