
Shipping Estimate
USA
- USA
- CAN
- USA
- CAN
Ships within 48 hours · Estimated delivery Jul 8 - Jul 13
For Your Every Summer RSVP, with Code: SUMMER15
Description
Diode Dynamics 20-21 Sierra 2500/3500 HD LED Sidemarkers Clear SetFeaturesPlug and play compatible with GMC Sierra HD 2020+ fender lightsDynamic startup sequence with animated effectFully illuminated housing with dual lens design for an even glowOptional Sequential turn signal feature with plug and play wiring harnessOEM grade construction and perfect fitmentEngineered and assembled in USAOverviewUpgraded Styling. These LED sidemarkers are a plug and play replacement for the factory fender lights illuminating the
FeaturesPlug-and-play compatible with GMC Sierra HD 2020+ fender lightsDynamic startup sequence with animated effectFully-illuminated housing with dual-lens design for an even glowOptional Sequential turn signal feature with plug-and-play wiring harnessOEM-grade construction and perfect fitmentEngineered and assembled in USAOverviewUpgraded Styling. These LED sidemarkers are a plug-and-play replacement for the factory fender lights illuminating the entire width of the housing for a distinctive look and brighter appearance. Choose from three lens color options to get the look you're after.Unique Startup. Both the standard and sequential models feature a unique startup sequence. Every time the sidemarkers turn on they illuminate in an intense amber color starting from the center then spreading to either side. Once they are completely illuminated they gradually return to a running light mode.Sequencing Turn Signal. Our sequential option provides an upgrade in functionality. Anytime you hit your turn signal the sidemarkers illuminate in a sequencing amber pattern to indicate signaling! The sequential option uses the included plug-and-play harness to power the fender lights using the headlight connector.OptionsAmber: These match your original sidemarkers and are DOT/SAE compliant.Smoked: A dark appearance great on black and grey vehicles.Clear: These are clear in color but still have the retroreflector optics.Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.4 ★★★★★
Based on 1653 reviews
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Product Reviews
★★★★★ 5
Not polyester! Thank you UA!
I never realized shopping for cotton socks in 2024 would be so difficult. Luckily I found these, and all the other Under Armour cotton socks and they are the best.
I cannot wear polyester, and these only have like 1%. I didn't realize our cotton is being replaced by polyester, and I don't like it. Bath towels don't work anymore either...
I need my cotton socks and towels, I love incandescent light bulbs, I'll always have a gas powered mower and leaf blower. Also butterfinger should've never their recipe. Just sayin...
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Reviewed in the United States on May 4, 2024
★★★★★ 5
Great quality
Size: Large, Color: True Gray Heather Assorted 2 (6-pairs)
The best socks, cotton quality
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Reviewed in the United States on June 28, 2025
★★★★★ 5
Great sock for everyday
Size: Large, Color: Black/Gray (6 Pairs)
So these are awesome but they are slightly thinner than older versions, shorter too. Just FYI if you a long time UA customer.
If you have never had their socks, I love them personally and only like one other brand better. They aren’t overly thick and they allow your feet to breath. I never have sweaty feet in these even in my warm boots. I also like that they don’t cut into my feet or get holes in the toes over long terms. The only reason I’ve thrown these out has been fraying near the ankle or someone (kids) thieving them.
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Reviewed in the United States on December 28, 2019
★★★★★ 5
LOVE THEM!!
Size: Small, Color: (001) Black / Black / Castlerock
LOVE! These socks are so comfortable! I wear a 5 in women's and a 3 in big kid shoes. The small fit me perfectly. I see where some say they run small but I can't say that was an issue for me. They are "snug" but thats what you want with a no show sock. I feel they have support vs the ones i used to buy at Walmart. They are very soft! I am actually buying more today and throwing my other ones in the trash!
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Reviewed in the United States on February 18, 2026
★★★★★ 5
So will not write down your foot
Size: Medium, Color: (001) Black / Black / Castlerock
I love these socks. They have a little bit of gel on the top of the heel for support in your tennis shoes and so your socks don’t write down. Very good quality.
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Reviewed in the United States on May 6, 2026
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