This assembly allows 3M Disc Pad Face Plate to be easily changed without removing the disc pad hub, allowing the operator to use a single tool for multiple applications from heavy grinding to finishing a workpiece.
Some face plates have ribbing on the bottom face. Ribbed face plates provide additional force when needed for optimal fracturing of the abrasive mineral. By reducing the area of contact, or pressure per square foot (PSI), ribbed face plates increase the grinding pressure of the abrasive with the same amount of operator effort, and extend disc life when dulling is a problem.
Choose a plate with the level of firmness needed for the application?a lighter density face plate for lighter weight grinding applications, and a harder density face plate for more heavyweight grinding applications. Using the correct face plate for the application ensures that the abrasive mineral will fracture as it should, maximizing the life of the abrasive. The plate comes in one of four different colors that indicate the density so the correct plate can be easily identified in the workroom: red = extra hard (for heavy grinding with the coarsest grades), black = hard (for heavy metal removal, large welds, etc.), gray = medium (for general purpose grinding and finishing), and white = soft (for finishing operations on flat or contoured surfaces).

3M 77197, Scotch-Brite™ Roloc™ Deburr and Finish PRO Unitized Wheel,TR, 3 in x 1/8 in x NH, 8C CRS+, 7100109130, 40/box
3M™ 94275, Versaflo™ Gold Coated Tinted Over-Visor with UV/IR Protection M-967N, 70071696879, 1 EA/Case
Air Turbine Tools 202DM - 1/8" Straight Hand Tool Series, 40,000 RPM, 32242
3M 33349, 641WY 1/4" X 24", 220 Mesh Diamond Cloth Belt, 7010534919
Dynabrade 95675 1/4" Male Plug with 1/4" NPT Male Thread
3M 22396, Roloc Disc 361F, 36 YF-weight, TR, 1-1/2 in, Die R150S, 7000045091
Dynabrade 52378 3" (76 mm) Dia. Straight-Line Type 1 Extension Wheel Grinder, 1 HP, 18,000 RPM, 3/8"-24 Spindle
Dynabrade 14360 Pneumatic Pipe Belt Finisher
Insize 5316-HM810, HORIZONTAL MICROSCOPE, 6974029775413
Dynabrade 40610 Electric Dynafile II Abrasive Belt Tool
Dynabrade 52380 4" (102 mm) Dia. Straight-Line Type 1 Extension Wheel Grinder, 1 HP, 15,000 RPM, 3/8"-24 Spindle
3M 24049, Wetordry Cloth Disc 281W, P1000 YF-weight, 8 in x NH, Die 800JM, 7000045052
Dynabrade 40378 Rubber Drive Wheel, Mini Dynafile II
Standard Abrasives 37446, PSA A/O Disc, 700595, 1-1/2 in x NH, 60, 7010331822
Dynabrade 11477 Dynabelter Abrasive Belt Tool, Heavy-Duty
3M 15145 Scotch-Brite Surface Conditioning Low Stretch Belt, SC-BL, A/O Medium, 1 in x 132 in, 7010364529
Dynabrade 52374 4" (102 mm) Dia. Straight-Line Type 1 Wheel Grinder, 1 HP, 15,000 RPM, 3/8"-24 Spindle 
