Specialized's EMT Pro MTB Multi Tool is the complete trail-side kit for nearly any mechanical issue. It includes 2, 3, 4, 5, 6, and 8mm Allen wrenches, a T25 Torx wrench for your disc rotors, a Phillips screwdriver, a chain tool, spoke wrenches and even a disc-pad separator and bottle opener. Plus, the tools are crafted from CNC-machined, chrome-plated steel for durability and the Allen key cores are hollow for extra weight savings.
I like that the tool is small and light. It would get you out of a bad spot. However after a wet ride even after being dried off it rusted very quickly. I dont like the chain tool I wouldnt buy it again.