Denso Iridium Long Life Spark Plugs SC20HR11 (Part 3444) — 4‑Pack, Fine-Wire Iridium for Extended Durability

DENSO 3444 (SC20HR11) Iridium Long Life spark plugs are a genuine 4‑piece replacement set engineered for extended durability and consistent ignition performance. These four authentic DENSO spark plugs (part #3444 / SC20HR11) are designed as direct-replacement ignition components for compatible gasoline engines. Built with an iridium fine-wire center electrode and factory-grade construction, they arrive in original DENSO packaging and include the necessary hardware for straightforward installation. Use the vehicle fitment tool to confirm compatibility for your make and model before purchase.

How does this DENSO iridium plug improve reliability?

Iridium-tipped electrodes resist wear better than conventional materials, helping preserve gap integrity and spark consistency over many miles. The DENSO factory process ensures each plug meets tight tolerances so ignition timing and combustion remain steady under normal driving conditions.

• Fine iridium center electrode for prolonged life
• Precision manufacturing for consistent spark gap
• Durable materials reduce electrode erosion
• Packaged as a matched set of four for uniform performance

What makes these plugs an easy direct replacement?

The DENSO 3444 (SC20HR11) is produced to OEM-equivalent specifications so it fits as a direct swap in engines specified for that part number. Each plug arrives with original DENSO packaging and hardware, and the included part code matches common factory references to simplify identification.

• Part number DENSO 3444 / SC20HR11 matches OEM references
• Includes original packaging and installation hardware
• Sold as a 4‑plug set for complete cylinder coverage
• Confirm fitment with your vehicle’s parts lookup before installing

How should I handle installation and maintenance?

Installation follows standard spark plug replacement procedures: remove old plugs, check and set the correct gap if needed, and torque to the manufacturer’s specification. Routine inspection during scheduled service intervals will help you monitor wear and determine the optimal replacement timing.

• Use a torque wrench to factory-specified torque values
• Verify or adjust gap only if required by your vehicle manual
• Replace coil boots or ignition leads if damaged during removal
• Follow manufacturer service intervals for inspection and replacement

Which performance characteristics should I expect on the road?

With iridium electrodes and precise manufacturing, these plugs aim to deliver stable ignition, reliable starts, and steady combustion across driving conditions. They are intended to help maintain engine smoothness and consistent throttle response when used in compatible engines.

• Consistent spark delivery for stable engine idle
• Improved longevity compared with standard copper plugs
• Maintains gap stability to support fuel efficiency trends
• Supplied as a matched four-pack for balanced cylinder performance

Who is this for: Drivers and technicians seeking an OEM-quality replacement spark plug set in a 4-pack—especially those who want extended service life from iridium electrodes and the assurance of genuine DENSO manufacturing. Ideal for vehicle owners replacing all plugs at once or shops performing scheduled maintenance; confirm vehicle compatibility before purchase to ensure proper fit.

FAQ

Q: Are these DENSO 3444 plugs genuine?

A: Yes — this listing contains genuine DENSO part #3444 (SC20HR11) spark plugs in original packaging.

Q: Do these plugs come as a complete set for a four‑cylinder engine?

A: Yes — the product is sold as a 4‑piece set intended to replace all spark plugs in applicable engines.