"Has what you need to complete field repairs so you can eat hot food."
Kit includes the parts you would need to address common issues with your stove. The case is compact and weight is low, even with a few extras that I added in (repair tools/supplies for other pieces of my camping kit). One thing I added is a small nylon bristled brush for cleaning - think toothbrush. I use it to keep soot build up at bay (works well on the jet nozzle).
"Haven't used it but will sure be glad when I need to"
It's got EVERYTHING I'd need to repair and maintain my Whisperlite Int'l on the trail short of a new stove and fuel pump. And, it's small enough that it fits in my Snow Peak Trek 1400 Al cookset along with my stove, heat reflector, windscreen and pot lifter.Even if you don't bring it with you into the backcountry, leave it in the car or include it in your bounce box on a thru-hike. You won't regret it.
"If you have an MSR stove, you need to get this."
Anyone that has one of these stoves will definitely need one of these as it will come in handy if your stove is not working correctly. When you are out in the field, it's raining, and no dry wood.... it's time to break this bad boy out to get your MSR stove going.