Sometimes bad things happen to good expeditions. All too often that bad thing is your stove taking a little trip to the island of Tango Uniform. Altitude, cold and your partner's gross incompetence are contributing factors.
For those unhappy times the wise expedition pre-pares for re-pairs. Larger expeditions can simply go redundant and bring multiple, preferably identical stoves. That might be overkill for two and three person teams, which is where the MSR XGK Expedition Repair Kit comes in handy. It's 4oz of prevention if you're carrying an MSR XGK stove, which is likely given its deserved popularity.
Pretty much everything you can replace on an XGK is included: flame spreader, jet cleaning tool, jet and cable tool, safety pin, pump cup and oil, fuel filter, check valve ball and spring and plug, fuel tube bushing, X and GK jets, shaker needle with cover, air tube, dip tube, 2 fuel tube o-rings, 2 fuel bottle o-rings and 2 control valve o-rings. Sorry, no partridge, no pear tree.