The sanding disks that I constantly use are made in the Dearborn,
Michigan, namely "Moore's", Abrasive discs. These are in the
diameter of 7/8 inch and are called ADALOX-Fine, or Medium, or
Coarse (grit). These can be used up to 30,000 RPM..These all have a
Brass Center..need I say more? If you buy cheaper, you get what you
pay for..right? ...Gerry!