It's not the same the jnc 950 put outs 2000 peak amps of power. No car batteries put out that kind of power. The high amp deep cycle battery is what keeps the starter turning time after time after time without needing to be recharged
We bailed a guy out tonight got a call I just left the shop pulled a U-turn a guy was stuck on the side of the main road alternator was burnt up and not charging the battery truck had 8 volts my buddy couldn't get the guys truck jumped with cables so I came down with the jump pack clean off the terminals and it started in three seconds.
The jump pack totally kicks ***
In a forum full of well informed auto guys of above average knowledge, I'm surprised I don't see this brought up more often when jump boxes are discussed. The peak amp rating on any box, in this case 2000 peak amps for the JNC 950, can can be ignored. It's an arbitrary number, the manufacturer can use any methodology they wish to determine it.
The important numbers to look for are CCA and CA, which are well defined and independently verified. CA is the number of amps sustained for 30 seconds at 32° F, while CCA is the same measurement at 0° F. So your JNC 950 is actually rated at 950 CA, hence the model number. As a generally accurate rule of thumb you can multiply by .8 to approximate CCA and you get 760, which matches the common Wal-Mart battery in my half ton.
Is the JNC more capable than my trucks battery? Yes, it has a higher reserve capacity. It's also not a true deep cycle battery, drop it below 10 volts too many times and it's toast.
The 950 actually uses the same internal battery as the 660, if I remember correctly, but has two of them. Why this doesn't double all the specs except voltage is not something I fully understand. That being said, both boxes are awesome and I own both.
. But regardless of that of the jump pack still kicks *** and no walmart truck batteries are going to do that for 5 years and counting 
. I am glad to learn a little more thanks for the lesson