Bosch N21 Spark Plug
Specs, cross-brand equivalents, vehicle fitment, and live prices for the Bosch N21.
Bosch
N21
BrandBosch
MetalCopper
Thread14mm
Reach19mm
Heat21
Gap0.031
The Bosch N21 is a 14mm thread, 19mm reach, heat range 21, copper electrode spark plug, pre-gapped to 0.031. These specifications are decoded from the Bosch part number and determine which plugs it safely cross-references to — a valid equivalent must match the thread, reach, seat and heat range.
Cross-reference equivalents
| Brand | Part | Metal | Buy |
|---|---|---|---|
| ACDelco | R44XLS | Copper | Buy |
| Champion | RN11YC | Copper | Buy |
| Denso | W14EXR-U | Copper | Buy |
| Denso | W14EPR-U | Copper | Buy |
| Champion | RN11YCC | Copper | Buy |
| Champion | RN12YC | Copper | Buy |
| Champion | RN12YCC | Copper | Buy |
| Champion | RN14Y | Copper | Buy |
| Champion | RN14YC | Copper | Buy |
| Motorcraft | AGS42C | — | Buy |
| NGK | BPR4ES | Copper | Buy |
| ACDelco | CR43CXLS | — | Buy |
| ACDelco | R43CXLS | — | Buy |
| ACDelco | R44CXLS | — | Buy |
| ACDelco | R45NS | — | Buy |
| ACDelco | R45XLS | — | Buy |
| ACDelco | R46XLS | — | Buy |
| ACDelco | R8600 | — | Buy |
| ACDelco | R8601 | — | Buy |
| Beru | 14R-9DU | — | Buy |
| Beru | Z82 | — | Buy |
| Bosch | 16SuperPlus | Platinum | Buy |
| Bosch | 27SuperPlus | Platinum | Buy |
| Bosch | W125TR30 | Copper | Buy |
| Bosch | W125TR30X | Copper | Buy |
| Bosch | WR1OLC | Copper | Buy |
| Bosch | WR9 | Copper | Buy |
| Bosch | WR9DC | Copper | Buy |
| Bosch | WR9DCX | Copper | Buy |
| Bosch | WR9DCXE.A.1,1 | Copper | Buy |
| FE35P | — | Buy | |
| FE45CPR | — | Buy | |
| FE45P | — | Buy | |
| FE45PR | — | Buy | |
| Champion | OE042 | Copper | Buy |
| Champion | OE045 | Copper | Buy |
| Champion | OE051 | Copper | Buy |
| Champion | OE161/T04 | Copper | Buy |
| Champion | OE45 | Copper | Buy |
| Champion | OE51 | Copper | Buy |
Showing the 40 closest cross-references of 66 total interchangeable part numbers for this plug.
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