Being a 4 in 1 product at this price I expected it to be cheap. I've only had it a day and haven't had the opportunity to test the jump start feature. But here's what I have tested. First, the flashlight. Completely useless feature. Not bright enough to use to light your way and would be shining directly in your face while trying to set the compressor settings if you were trying to use it as a safety light. The compressor seems to be pretty decent. I was able to air a rear motorcycle tire from completely flat to 33psi in just a couple minutes, and this was done with less than 25% battery left. Reason it was so low is the power bank feature, which is another complete waste. With a full charge I plugged my phone (iPhone 14 pro max) up at 10%, and by the time my phone reached 40% the battery on the jumper had gone from fully charged to less than 25%. This makes me seriously question what it will be capable of in regards to jump starting a vehicle. For the money I'd say it's as good as any other portable compressor like it, and it may work in a pinch as a jump starter. But there are plenty of dedicated jump starters in this price range much better, so except for wanting an emergency compressor with some bonus features I wouldn't spend your money on this thing. Also, although it isn't more than an irritating thing to add, the charging cable that came with it doesn't work at all, having tried it with several different devices. I'll update my post soon if the jump starter changes my mind.