Luckily, I haven't had to use it to start anything "yet". I've only used it as a portable charger for cameras, cell phones, etc.
I have the Microstart pro by Antigravity which is they're smallest version. The largest version will start a Diesel engine, and still fit im the glove box!
Do all guys know how to jump start your car?
Click this link to learn much: How to Use a Portable Jump Starter - Jump Starter Expert
What the last time you use your jump starter?
Yesterday! I was pulling in to Walmart to park. There was a car with the hood open and an auto dept guy with a small jump starter - No Go. I asked "does she need help"? He said his wasn't doing the trick, so I took out my 1000 amp Schumacher jump starter and the car started easily.
As I was walking back to my car, she said "you just saved a life, I am taking my husband to dialysis".
"You cannot live a perfect day until you do something for someone who will never be able to repay you" John Wooden