Jump Starter Adapter for Makita 18V Li-ion Battery Automotive Batteries Booster with 12V Jumper Cable Clamps for 3

So, I will say right off the bat that I have not jump started a car yet with this device. I haven't had a need to yet, so haven't really wanted to put my car in the condition of needing this in order to test. I will say, however, that this does output the advertised voltage and knowing Makita batteries this does seem like it could put out enough juice to charge a weak battery enough to get a start. Plugging a battery in, this device immediately shows a green light meaning it is ready to be attached to a weak / dead battery. I can attach it to a battery and get the charging indicator light also (flashing), so that all appears to work. But, I almost immediately get the steady green again which means your battery is ready to start your car (which checks out). When unplugging the Makita battery, the light flashes red quickly, which is the indicator for low source battery, so that seems to work correctly too. The only thing I cannot really test at the moment is the main function - charging a battery to provide a start. For now, I will keep this at the ready in case it is needed. Seems to work as far as I can test it, and it seems like a convenient piece of kit. Read more

I too have not tried this to start my vehicle as it luckily has not been needed. But it is nice to have around so as not to pull out the old charger and wait for a slow amperage charge. The Makita battery I have is non-OEM and still fit well onto the device. The light shows green to indicate it has a charge, I guess. Glad to have this around for my small SUV but I’m not sure it would work on my diesel truck with 2 12V batteries, hoping I don’t have to find out. Read more