- Foglight / Headlight bulb replacement
- Correct optical focus for increased output with no added glare
- Perfect fitment, no modification needed
- Designed and validated to OEM lighting standards
- Engineered and Assembled in USA
SL1 LED Bulbs
Reliability. Every part of the SL1 LED was designed for reliability, from the custom wiring with strain reliefs and solderless terminals, to the exclusive zinc castings, to the reinforced high-temperature PP-GF plastics (the same used in halogen bulb bases). Each component was designed and tested, with dozens of variations of each component reviewed until we achieved the maximum performance possible. Finally, the SL1 was put through its paces in our environmental testing chambers - where the bulb successfully performed through dozens of thermal cycles, from -40 through 85 degrees Celsius (-40 to 185F). Whether you're in the Sahara or northern Canada, the SL1 will keep performing for years, and is backed by a three year warranty.
Aftermarket or OEM? If you're looking to improve visibility on your vehicle at night, you've probably found many options for LED upgrades. Most bulbs on the market are too big to install, don't work with the electrical system, and have no focus or hotspot in the beam pattern. Even if they come close on those aspects, they still aren't anything close to the quality you would find with factory-installed lighting. Like most aftermarket products, most LED bulbs are not engineered and tested for long-term reliability.
Street Legal Output. Don't be fooled by high lumen numbers. Your vehicle's lamps are designed as a system, to focus light. If the light source in that system is out of focus, it doesn't matter how bright it is. You won't have a focused hotspot of light to shine down the road, you'll just have more glare. To correct this, the SL1 LED bulb was engineered with advanced optical design software, which simulates each ray of light in a process known as "ray tracing." Using this tool, our engineers perfectly matched the filament location, allowing the SL1 LED to focus light just like your original bulb, preserving the focus and hotspot, with no added glare. This is a safe, functional output, in compliance with photometric standards.
Fitment. With its patented design, the SL1 LED fits where other bulbs won't, without cutting or modification. There's no hanging metal straps, just a compact bulb that plugs right in, with an exclusive reinforced shroud to keep the heat off any other components or wiring. Only slightly larger than a standard halogen bulb, it fits behind dust caps and in tight spaces. The driver and bulb are tested to function when sealed inside - no worries about heat buildup! The base sizes on the bulb are also are keyed for exact applications, not one-size-fits-all, and the compact driver easily tucks away.
Driven. Rather than a simple buck regulator found on other bulbs, the SL1 uses a unique boost-mode circuit, which prevents thermal imbalance in the LEDs over time - again, just like you would find in OEM LEDs. It also has transient protection for long life in automotive circuits. Diode Dynamics engineers also analyzed dozens of OEM electrical systems, and added current-monitoring circuitry to mimic the electrical characteristic of halogen bulbs, drastically reducing the need for CAN-BUS adapters (though they're still needed on some applications).
I put this bulb in both my 2019 Tacoma and my Camry. They work perfect. Extremely bright and a good cut line in the beam. There is no lost light. The beans is wide and focused right where it should be. I highly recommend these bulbs.
Tried a bunch of different led bulbs and none fit. These fit nicely behind my dust covers on my ram. Thank you!
I picked up a pair of H11 SL1s from Ess K back in 2018 for my 18' Colorado low beams and am now using them in my 2019 Ford Ranger Fog lights. They are a good sized bulb and have decent light output. They do have a little bit of a hum to them because of the fans but you shouldn't notice it inside the vehicle when driving. Pretty hard to complain with 2.5ish years of use and no signs of quitting yet.