The unique design of the file cross-section allows the sharpening of a multitude of different items.  
 
The sharpening rod can be retracted and stored within the aluminum case.  Simply twist the sleeve to lock/release the tool.  
 
Use the Flat Face of the tool to produce a razor sharp edge on any number of difficult to sharpen tools.  
 
Use the V shaped grooved channel for precision point sharpening e.g. darts, fishhooks, scribers, bradawls, etc.  
 
Use the curved side to sharpen serrated blades or to smooth any other curved surfaces even glass chips.