The Oregon Multi-Tool has 9 tools in one that allows the user to work on chain saws, cutoff saws, trimmers and blowers in the field.
The tool easily fits in your pocket (4 1/2″ long) and contains a large screwdriver for bar adjustment a T27 Torx for all bolts on a Stihl chain saws and cut off saws, a small screwdriver (for fuel and bar oil adjustment), a bar groove cleaner, a 4mm Allen Wrench (for work on Echo, Jonsered, Husqvarna and most other saws), and has a 13mm (1/2″) socket that will fit a bar nut on a half or full wrap handle Husqvarna saw. The other end of the tool has a 19mm deep socket for Stihl bar nuts and spark plugs on most saws, that can be reversed with a 10mm socket for Echo bar nuts.
It comes with a nylon sheath so you can hang it on your belt and take it with you. Additionally it can be used as a file handle, there is a set of holes in the socket for a chain saw file to be placed.