I have two one in car one in RV one in RV is a good size (900 peak amps) AGM type (Lead acid) and is big and heavy.. In need a new battery clamp for one of the wires.
The one in the car is a light weight Lithyum type.
Have used 'em several times for one reason or another. not always personal use.
Been carrying one for over 20 years (only had RV 15) use the big one as a 'portable car' from time to time when I need 12 volt "out and about" works great. This is my 3rd one I think first one was while I told cops where to go died of old age. 2nd one was used for a while at a towing company to jump start customer's cars... It came with me when I left their employ.. this is #3 or 4 not sure which. Very handy boxes.
Oh and you can replace the battery I've done that on this one.