Support Block for Diamond Sharpening Stones

This is a block and angle guides for diamond sharpening stones which are 15 cm/5.91 inches in length, 6.3 cm/2.48 inch, and 0.1 cm/ 0.04 inches in height.  These are fairly widespread and can be found on many outlets online.  The stones themselves are actually metal plates, and as such they've pretty thin.  I've always found it difficult to use them on a flat surface, since the handle or hilt of the knife often makes contact with the surface itself.   This allows you to raise the stone up off the surface and give you the clearance you need to sharpen.

There are also angle guides which snap on to the block, both for sharpening diagonally across the surface, and straight across.