Series | 
                                                                        N/A 15500 | 
                                                                                Cone Part Number | 
                                                                        N/A 15578 | 
                                                                                Cup Part Number | 
                                                                        N/A 15520-B | 
                                                                                Design Unit | 
                                                                        N/A Inch | 
                                                                                Cage Material | 
                                                                        N/A Stamped Steel | 
                                                                                Related Assembly Number(s) | 
                                                                        N/A 15578-90023 | 
                                                                                d - Bore | 
                                                                        N/A 1 in25.40 mm | 
                                                                                D - Cup Outer Diameter | 
                                                                        N/A 2.2500 in57.150 mm | 
                                                                                D1 - Flange Outer Diameter | 
                                                                        N/A 2.4022 in61.016 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 0.1563 in3.970 mm | 
                                                                                T1 - Bearing Width to Flange | 
                                                                        N/A 0.3125 in7.938 mm | 
| R - Cone Backface "To Clear" Radius1 | N/A 0.050 in1.300 mm | 
| r - Cup Backface "To Clear" Radius2 | N/A 0.06 in1.5 mm | 
                                                                                da - Cone Frontface Backing Diameter | 
                                                                        N/A 1.2 in30.5 mm | 
                                                                                db - Cone Backface Backing Diameter | 
                                                                        N/A 1.28 in32.5 mm | 
                                                                                Da - Cup Frontface Backing Diameter | 
                                                                        N/A 2.40 in59.94 mm | 
                                                                                Ab - Cage-Cone Frontface Clearance | 
                                                                        N/A 0.1 in2.5 mm | 
                                                                                Aa - Cage-Cone Backface Clearance | 
                                                                        N/A 0 in0 mm | 
| a - Effective Center Location3 | N/A -0.2 in-5.1 mm |