The factory third brake light on your 2004.5-2005 GM 6.6L is often overlooked, but upgrading to an aftermarket LED version can make a significant impact on your GM 2500HD/3500HD. Whether you're replacing a worn-out stock light or seeking improved visibility and style, Alligator Performance offers a variety of LED third brake lights to meet your needs. With easy installation and enhanced light output, these lights provide a hassle-free upgrade that boosts both lighting performance and the look of your GM. Pair your new high powered 3rd brake lights with our selection ofTaillights!GM Duramax Fitments: 2004, 2005 GM 6.6L Duramax.Submodel Fitments: WT, Custom, LT, LTZ, High Country, 1LT, 2LT, Pro, SLE, SLT, AT4, Denali.Some exceptions apply, please see individual product pages for specific fitments.