Be leery of the cheap ones. These are Lithium Ion Batteries so they don't like sitting discharged and will often do so at places like the Home Depot and Lowes. I returned a couple of those before I picked up the one I have off Amazon.
I have an Antigravity Micro-Start(tm). An older model so I'd peruse their newer ones and buy it off Amazon or something (A bit cheaper).
https://shop.antigravitybatteries.com/productline/micro-starts/Bonus on the one I have is that it's a pretty decent flashlight and I can charge my phone off it.
Works great on the bikes a couple cars and my truck once.
The only time it failed me was on a shorted battery recently, wouldn't register it was hooked up, but that's the nature of a short so not much for it.
Jumping from cars? Yup done it. Best to have the car not running. I have a pair of bike sized jumper cables kicking around from before I got the Micro-Start(tm).
There are some other nifty ones out there, particularly the NoCo units which will sell ya a pigtail that'll let ya not have to use the clamps to jump your bike.
My only gripe with them is their stuff is proprietary vs. SAE connectors.
Do remember that these are LiIon Batteries at their core so they don't like being below 40F for long periods of time & you do need to charge 'em now and again.
Caveat Emptor of course folks my info's accurate but it's been a couple years since I've taken a close look at what's outthere.
