Ceramic Knife Sharpener and Honer - MakeEdge Pop-Up system by the makers of Crushgrind Mill Mechanisms
The MakeEdge Pop-Up system is designed to be installed in butcher blocks and cutting boards by simply drilling a 1-1/2" diameter hole 4-1/8" deep. It's then installed, and held in by pressure on the ribs on the outside of the unit.
It's spring loaded, which allows you to press it in a bit, and then it pops out to allow you to sharpen your knives, then pressed back in where it sits flush.
The sharpening material is 2 ceramic pieces inside, which can be flipped after years of use, to get the other side to do more sharpening. Each side has a 5 year guarantee, which means 10 year guarantee total.
These are made by Ideas Denmark, who have been making top quality ceramic kitchen tools for years now.