Resin to Resin bonded
These are B weight paper backing abrasive sheets of AO with the additive Stearate. This Stearate additive helps resist loading and smooths out the cut. It is an expensive additive but worth it. The abrasive is white in color. This abrasive is especially useful with ivory, white micarta or light colored wood. This product was developed for the boating industry as it resists loading so well. It will last longer than most on micarta or G10 where typical paper loads up quickly.
From the Klingspor Factory:
These are our 'STEARATE' sheets. They are Aluminum Oxide, resin bonded, paper-backed for long life and tear-resistance. This material is recommended for bare wood sanding and autobody use. Applications include sanding of bare metal, primer surfacer and between coats of paint, lacquer and shellac. Also useful on sanding of solid surface countertops such as CORIAN, FOUNTAINHEAD and AVONITE. Our very high quality Zinc Stearate material, added in the size coat, will outperform virtually all competitors.