DuraGRIT discontinued carbide discs in grit grades finer than 80 grit because of lack of demand.
Our carbide sanding discs excel at rough sanding and leveling. They hold their grade from beginning to end of a sanding job and last a very long time.
DuraGRIT recommends using 46, 60, and 80 carbide discs to do the lion-share of leveling and smoothing of surfaces, followed by ordinary, flexible backed disposable discs in fine grades 120 and above for fine finishing, as they are not removing much material at these grades and do a fine job.
(Please note the vacuum hole pattern is compatible with most 5" diameter sanders with a 5 or 8 vacuum hole pattern, but not Festool® orbital sanders)