NGK ARF4 Spark Plug
Specs, cross-brand equivalents, vehicle fitment, and live prices for the NGK ARF4.
The NGK ARF4 is a 18mm thread, gasket seat, heat range 4, copper electrode spark plug. These specifications are decoded from the NGK 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 |
|---|---|---|---|
| Denso | T20R-U | Copper | Buy |
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