This assembly allows the 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 inch (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 47184, Polyurethane Adhesive Sealant 550FC Fast Cure, White, 350 mL Sausage Pack, 7100197992, 12/Case (Use with 400A-2K APR, Nozzles Not Included)
3M 35832, Hookit Dust Extraction Flexible Radius Sanding Block, 273 mm x 66 mm, 7100256499
3M 21543, Scotch-Brite Roloc Clean and Strip XT Pro Extra Cut Disc, TR, 2 in x NH, A XCS, 7100179815, 60/box
Insize 6315, MICROMETER MEASURING FORCE DETECTOR, 6928640351143
3M 07959, Sanding Screen, 100 Grit, 7-7/8 in x 3/16 in, 7100160279
3M 08025, Adhesive Sealant 740 UV, Black, 600 mL Sausage Pack, 7100057385, 12/Case
3M 16609, Accuspray Atomizing Head, Red, 2.0 mm, 7000045543 (4 Nozzles/Kit) (6 Kits/Case)
3M™ 07012, Supplied Air Hose W-9435-100/07012(AAD), 100 ft, 3/8 in ID, Industrial Interchange Fittings, High Pressure, 7000005375, 1 EA/Case
3M 53034, 663FC, 3/4" X 90", 20u, Diamond Trizact Belt 7100205969
Dynabrade 90873 2" Dia. Medium NWN DynaBrite Locking-Type Disc, 25/pack
Dynabrade 14360 Pneumatic Pipe Belt Finisher
3M™ 53797, Flexible Diamond Belt 6451J, 1/2" Dia x 18" L, M125 Micron, Type G, Pattern B2, 7010509272
3M™ 72013, Adapter 529-04-50, 110-120 VAC, 7000131705, 1 EA/Case
3M 22405, Roloc Disc 361F, P100 YF-weight, TR, 3 in, Die R300V, 7000045102
3M™ 17323, Versaflo™ Respiratory Helmet Assembly M-407, with Premium Visor and Flame Resistant Shroud, 7000002395, 1 EA/Case
3M 11411, Roloc Disc 361F, 50 YF-weight, TR, 1 in, Die R100N, 7000045095 
