NGK 99404 Spark Plug
Specs, cross-brand equivalents, vehicle fitment, and live prices for the NGK 99404.
The NGK 99404 is a 14mm thread, 19mm reach 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 | SK20PR-A8 | Iridium | Buy |
| Denso | K20PSR-B8 | Copper | Buy |
| Brisk | 1622 | — | Buy |
| Brisk | P4 | — | Buy |
| Champion | CCH9802 | Copper | Buy |
| Champion | OE179 | Copper | Buy |
| Champion | OE179/T10 | Copper | Buy |
| Denso | 1UN718110 | Copper | Buy |
| Denso | 267700-2340 | — | Buy |
| Denso | 267700-4380 | — | Buy |
| Denso | 3403 | — | Buy |
| Denso | S21 | Copper | Buy |
| Denso | SK20PR-F8 | Iridium | Buy |
| NGK | 6066 | — | Buy |
| NGK | FR6EI-11 | Copper | Buy |
| K6RTJP | — | Buy |
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