Gesshin 100 XL Stone Fixer

Stone fixers are a very important part of the sharpening process.  Keeping one's stone flat helps with angle consistency, and is absolutely crucial when working on wide bevel and single bevel knives.  Though I often use diamond stone fixers, I wanted to have an alternative for those who don't like to use diamond.  Some of the downsides of diamond flattening stones are that they tend to be smaller in size (sometimes smaller than the stones they are flattening) and that they tend to wear more quickly on coarse stones.  This addresses both of those issues.  Though it isn't quite as fast as a diamond stone, this one is pretty close.  However, it works great on really coarse stones and, as I was happy to find out, on specific types of diamond stones that I like to use (for example our 1000 and 6000 stones, as well as the 800 grit vitrified diamond stone I use every day).  
Both sides of this flattening stone can be used.  The side with grooves is designed to not stick on very muddy stones, while the non-grooved side has a bit more surface area and cuts a bit faster.  This can be used to flatten stones ranging from very coarse to ultra fine.  In the case of natural stones, you may want to refinish the stone surface after flattening, using a nagura or something similar.  This is not necessary with synthetic stones, though you are always welcome to do so.
Please keep in mind that this is essentially a very hard and very coarse synthetic stone, and while it is designed to be used for flattening, from time to time, this stone will need to be flattened as well.  This can be done in a variety of ways, including using a flat section of the sidewalk outside to flatten this.  You can also try extremely coarse sand paper on a hard/flat surface.  Lastly, the non-grooved side of this stone can be used as an ultra coarse stone for very serious sharpening repairs.