According to the Sylvania bulb guide, the 21+ Frontier uses an H11 bulb.
While our team hasn't tested for fitment, we do offer our SLF LED bulb in 3K selective yellow in an H11 size.
Features Direct replacement for factory incandescent bulb Correct optical focus for Street Legal Output Plug and play, simple installation Engineered and assembled in the USA Available in 6000K cool white and yellow Overview Upgrade. If you're looking to replace your factory yellowish...
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If there is a compatiablity issue, our team offers a hassle free return with no restocking fee for the first 30 days!