Diode Dynamics DD0492P H4 SL2 Pro LED Bulbs – White – Pair

Upgrade compatible H4 lighting with the Diode Dynamics DD0492P H4 SL2 Pro LED Bulbs. Designed as a compact replacement for H4 halogen bulbs, the SL2 Pro combines advanced LED technology, integrated cooling, and a fully integrated design without external drivers or loose wiring.

The H4 configuration provides both high-beam and low-beam functionality in the same bulb, operating similarly to the equivalent factory H4 halogen bulb. 

Key Features

• H4 / 9003 bulb size
• SL2 Pro LED technology
• White LED output
• High and low beam functionality
• Direct replacement design
• Compact fitment
• Fully integrated construction
• No external driver or loose wiring
• Integrated top-mounted cooling fan
• Engineered for correct optical focus
• Two LED bulbs included
• Limited Lifetime Warranty
• Designed and engineered in the USA

SL2 Pro LED Technology

Diode Dynamics developed the SL2 Pro as an evolution of its previous SL1 LED bulb. The SL2 Pro uses next-generation Thermal Separation Technology (TST) LEDs designed to reduce thermal resistance while maintaining optical focus.

The bulb is engineered to position its light similarly to the original halogen source, helping maintain the intended beam pattern rather than simply producing uncontrolled additional light.

An integrated top-mounted fan manages heat within a compact, fully integrated package, eliminating the need for a separate external driver.

H4 High & Low Beam Functionality

The H4 bulb format combines high and low beams into a single bulb. Diode Dynamics confirms that its SL2 and SL2 Pro H4 bulbs are designed to behave like the corresponding halogen H4 configuration, providing both functions from the same bulb.

Fitment

Manufacturer Part Number: DD0492P
Bulb Size: H4 / 9003
Series: SL2 Pro
Color: White
Quantity: Pair

DD0492P is used across multiple vehicle applications that utilize compatible H4 bulbs. Diode Dynamics currently lists vehicle-specific applications including select Toyota, Honda, Mazda, Nissan, and other vehicles.

Always confirm your vehicle’s year, make, model, headlight configuration, and factory bulb size before ordering.

What’s Included

• Two (2) Diode Dynamics H4 SL2 Pro LED bulbs

Installation

The SL2 Pro features a compact, integrated design intended as a direct replacement for compatible factory H4 bulbs. Installation requirements and available clearance can vary by vehicle.

Always verify bulb access, electrical compatibility, dust-cap clearance, and vehicle-specific requirements before installation.

Important U.S. Headlight Use Notice

LED replacement bulbs installed in halogen headlamp housings are not DOT/FMVSS108 compliant for street-legal headlight use in the United States.

Diode Dynamics specifies that its LED replacement bulbs are legal in the USA for fog-light use only. International regulations vary by country.

Warranty

Diode Dynamics SL2 Pro LED bulbs are backed by a Limited Lifetime Warranty, subject to the manufacturer’s warranty terms and exclusions.

California Proposition 65 Warning

WARNING: This product may expose you to chemicals known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, visit www.P65Warnings.ca.gov.