381C discs have an aluminum oxide abrasive on a tough, but flexible, fibre-backed disc.
This is 3M's value line of general purpose grinding dics.
• A good performing disc for use on well-cured fiberglass, wood, and metals
• 300 Series aluminum oxide abrasives are mid-range abrasives with good performance
• Closed coat makes these discs better suited for dense, non-loading substrates
• Offered with traditional center hole mounting, as well as popular 5/8-11 TN quick change attachment versions
• Priced by the box
User Tip — Especially with coarser 36 and 24 grits, we recommend the use of an extra hard red ribbed backing plate for cooler running and prolonged disc life; see Related Products, below.
For higher performance discs, consider 3M's 785C (Cubitron and aluminum oxide blended abrasive) for aluminum, fiberglass, or stainless steel, and 501C (aluminum zirconia abrasive) for carbon steel; see Related Products, below.