MRC Type Target Backing Plate Configurations TARGET DIAMETER MATERIAL OEM Equivalent PART NUMBER   Inches (mm) Round Type A ("O" Ring Sealed) *1 (25.4) Stainless Steel 808-17-200 *2 (50.8) Stainless Steel 808-18-200 *3 (76.2) Stainless Steel 808-19-200 *4 (101.6) Stainless Steel 808-20-200 5 (127.0) Stainless Steel 808-03-005 6 (152.4) Stainless Steel 808-03-006 6 (152.4) Copper 808-25-006 6.5 (165.1) Copper 828-06-100 8 (203.2) Copper 828-25-003 Internally Water Cooled 8 (203.2) Stainless Steel 808-26-100 10 (254.0) Stainless Steel 808-68-100 12 (304.8) Stainless Steel 808-63-100 14 (355.6) Stainless Steel 808-89-100 15 (381.0) Stainless Steel 808-71-100 16 (406.4) Stainless Steel 808-90-100 Round Type B (No Water to Vacuum Seals) *1 (25.4) Stainless Steel 828-07-100 *2 (50.8) Stainless Steel 828-08-100 *3 (76.2) Stainless Steel 828-09-100 *4 (101.6) Stainless Steel 828-10-100 5 (127.0) Stainless Steel 808-87-100 6 (152.4) Stainless Steel 808-88-100 8 (203.2) Stainless Steel 808-60-100 10 (254.0) Stainless Steel 808-69-100 12 (304.8) Stainless Steel 808-67-100 14 (355.6) Stainless Steel 808-94-100 15 (381.0) Stainless Steel 808-72-100 16 (406.4) Stainless Steel 808-93-100 MRC 900/600 Rectangular Type B (No Water to Vacuum Seals)   Planar Copper 899-00-382 INSET®1   Copper 828-36-100 Mag. Matls. Planar   Copper 869-06-002 *  Note: Target Diameters of 1" thru 4" have 5" O.D., reduced in center to appropriate target diameter. 1. Note: INSET ® is a registered trademark of Praxair Corp.