Carbide Skiver.  The Carbide Skiver is a cutting insert as are the files.  However, they are used only one at a time!  A stone can be used in the other pocket when using a carbide, never another carbide, it is too much, over-kill.  But unlike files, they can be re-sharpened (see Maximizing the Life of the Inserts) an infinite number of times, and they can be rotated to use up to 16 cutting surfaces before needing re-sharpening.   

You can observe these two cutting edges on the carbide that show wear, one edge more than the other.  As carbide edges wear, they get rounded and shiny.  This carbide will need re-sharpening soon. (See Maximizing the Life of the Inserts below) If you do a lot of cutting with the Ski Sharp, get a Carbide Skiver, they cut edge metal like butter and last forever.  They are a one time investment.

The Carbide Skiver feels relatively dull and ineffective if you roll it in your fingers, but don't be fooled. It is a very aggressive cutter because of its relative hardness to the ski edge.  It is easy to "over-do" with the carbide so use it with care and be conservative with it.  Use it with a light touch, let it cut at its own pace, don't rush it.

The Carbide Skiver is a flat carbide blank, this makes it re-sharpenable an infinite number of times.  However, a white plastic shim piece needs to be used with it to create a cutting tooth.  This is the Carbide Skiver in the base edge pocket.

This is the Carbide Skiver in the side edge pocket. Again, notice the white shim piece used to form a single cutting tooth.  Keep in mind, the Carbide Skiver is mostly used in the side edge pocket for sharpening purposes. The Carbide Skiver is used in the base edge pocket only when cutting in base edge bevel initially and perhaps occasionally when re-checking base edge bevel. 

It is important to use this insert correctly when cutting in bevel!  Cutting in bevel requires a number of passes, taking some edge metal each time, until your bevel selection is achieved.  However, if you continuously use the carbide in one direction you will develop striation lines on your edges, small lines that look like skip marks.  You can avoid this by reversing direction with the carbide each pass along the ski.  Say the first pass down the edge is cutting from tip to tail. You should then reverse the carbide in the Ski Sharp and cut from tail to tip.  This way you prevent the striation marks in your edges.

The Carbide Skiver leaves a very nasty burr.  After using it, major polishing is required to remove the burr; you can also polish it out lightly by hand.

The Carbide Skiver is not for cutting through rock damaged edge sections. Rock damaged edge sections must first be polished thoroughly with the Ruby Sharpening Stones.