From the makers of Moore's Snap-On Discs, these 5/8" diameter, coarse, Adalox (aluminum oxide) abrasive discs have a paper backing and a 1/16" arbor hole.  They are to be used with screw mandrels (not included).   Adalox is recommended for use with Acrylics, Gold and other metals.  Sold in boxes of 300 discs.