Sioux Force Tools grinders are generally used for sanding and polishing. They are made from lightweight materials such as aluminum so that they are that much easier to use.
Pencil grinders are designed for the more sensitive materials but can be used for the same purposes as a general grinder.
Sioux Force Tools engravers are air powered tools and are made from stainless steel for greater durability. These tools are generally used for industrial application for engraving or writing words on tough materials.