Denso Iridium TT Spark Plugs IKH16TT 4-Pack — Long-Life 0.4mm Centre Electrode, Improved Ignitability

These Denso Iridium TT plugs combine a 0.4 mm iridium center electrode and a 0.7 mm needle-tip ground electrode with Denso's 360-degree laser welding and a high-iridium alloy to maximize ignitability, reduce misfires, and extend service life. Built with a robust alumina insulator, machine-rolled threads, and a copper-glass gas-tight seal, the IKH16TT set is engineered for drivers who want consistent starts, improved throttle response, and stable combustion over long intervals.

How do these plugs improve engine response and fuel use?

The Twin-Tip (TT) design concentrates spark energy at a very small contact point, helping ignite the air/fuel mixture more completely. That more consistent ignition can translate to smoother acceleration and modest gains in efficiency under typical driving conditions.

• 0.4 mm iridium center electrode for sharper spark
• 0.7 mm needle-tip ground electrode reduces flame quenching
• Improved ignitability aids throttle response
• Consistent combustion can support better fuel economy trends

What makes the Denso IKH16TT durable for long service intervals?

Denso uses a patented high-iridium concentration alloy and 360-degree laser welding to bond the tiny iridium electrode securely, resisting wear and maintaining a reliable gap. Combined with a purified alumina insulator and machine-rolled threads, these features reduce failure modes that shorten plug life.

• High-iridium alloy for abrasion and heat resistance
• Laser-welded electrodes minimize mechanical loss
• Purified alumina insulator for thermal strength
• Machine-rolled threads prevent seizing during service

Are these plugs easy to install and compatible with maintenance routines?

The IKH16TT plugs include design details that simplify installation and help ensure reliable reinstallation. They arrive pre-fired and feature machine-rolled threads and a five-rib insulator to reduce flashover and installation problems for DIYers and technicians alike.

• 100% pre-fired for consistent quality out of the box
• Machine-rolled threads reduce cross-threading risk
• Five-rib insulator reduces surface tracking/flashover
• Copper-glass seal provides a gas-tight bond to prevent leaks

How should I choose these plugs for my vehicle?

Select the IKH16TT when your vehicle’s manufacturer lists compatible iridium or equivalent fine-electrode spark plugs, or when you want extended replacement intervals with reliable performance. Always confirm thread size, reach, and heat range match your engine specifications before purchase.

• Confirm OEM-equivalent part numbers and specifications
• Check thread size, hex size, and reach for fitment
• Use in engines designed for fine-electrode iridium or platinum plugs
• Follow torque and gap recommendations during installation

Who is this for: The Denso IKH16TT set is aimed at vehicle owners and mechanics seeking a high-durability spark plug with enhanced ignitability—drivers who value long service intervals, reliable cold starts, and improved throttle feel without frequent replacements. It's suitable for cars engineered to accept iridium twin-tip or fine-electrode plugs and for anyone performing regular maintenance who wants factory-quality components that reduce installation risks and deliver steady combustion performance.