Series | 
                                                                        N/A 18600 | 
                                                                                Cone Part Number | 
                                                                        N/A 18690 | 
                                                                                Cup Part Number | 
                                                                        N/A 18620-B | 
                                                                                Design Unit | 
                                                                        N/A Inch | 
                                                                                Cage Material | 
                                                                        N/A Stamped Steel | 
                                                                                d - Bore | 
                                                                        N/A 1.8125 in46.038 mm | 
                                                                                D - Cup Outer Diameter | 
                                                                        N/A 3.1250 in79.375 mm | 
                                                                                D1 - Flange Outer Diameter | 
                                                                        N/A 3.3086 in84.038 mm | 
                                                                                B - Cone Width | 
                                                                        N/A 0.6875 in17.463 mm | 
                                                                                C - Cup Width | 
                                                                        N/A 0.5313 in13.495 mm | 
                                                                                C1 - Cup Flange Width | 
                                                                        N/A 0.1406 in3.571 mm | 
                                                                                T1 - Bearing Width to Flange | 
                                                                        N/A 0.2968 in7.539 mm | 
| R - Cone Backface "To Clear" Radius1 | N/A 0.11 in2.8 mm | 
| r - Cup Backface "To Clear" Radius2 | N/A 0.06 in1.5 mm | 
                                                                                da - Cone Frontface Backing Diameter | 
                                                                        N/A 2.01 in51 mm | 
                                                                                db - Cone Backface Backing Diameter | 
                                                                        N/A 2.2 in56 mm | 
                                                                                Da - Cup Frontface Backing Diameter | 
                                                                        N/A 3.05 in77.47 mm | 
                                                                                Ab - Cage-Cone Frontface Clearance | 
                                                                        N/A 0.09 in2.3 mm | 
                                                                                Aa - Cage-Cone Backface Clearance | 
                                                                        N/A 0.01 in0.3 mm | 
| a - Effective Center Location3 | N/A -0.08 in-2 mm |