| Part Number | OEM # | Length | Inlet/Outlet | Sensor | Additional Info |
| BN-521LP | X24 | 3 bolt in, 2 bolt out | 1 sensor below inlet flange, 1 sensor between bodies | hanger below rear body | |
| BN-521RP | X24 | 3 bolt in, 2 bolt out | 1 sensor below inlet flange, 1 sensor between bodies |