GMC Sierra 3500 HD Tonneau Cover - Undercover - Flex Folding - Black Textured - `20-`26
GMC Sierra 3500 HD Tonneau Cover - Undercover - Flex Folding - Black Textured - `20-`26
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GMC Sierra 3500 HD Tonneau Cover – UnderCover Flex Folding, Black Textured (2020–2026). This tri-fold hard cover delivers a low-profile look and practical bed security for 8 ft 2 in long-bed models.
FRP composite panels offer a strong, light solution with high dent resistance, resting inside the bed rails for a tidy fit. Built-in prop rods let you drive with the cover fully open when you need full-bed access. Clamp-on hardware simplifies setup, and the entire cover can be removed in seconds with no tools. Rubber seals and drain tubes help route water out of the bed, while buckles and straps keep panels secured in the partially open position.
Features
- Fitment: 2020–2026 GMC Sierra 3500 HD, 8 ft 2 in bed
- Ultra-low profile design inside bed rails
- FRP composite panels for strength and dent resistance
- Prop rods for driving with cover fully open
- Clamp-on install; tool-free removal; seals and drain tubes
- Textured black finish; 3-year manufacturer warranty
Questions or planning a build? Call our Austin, Texas or Los Angeles, California area teams—we offer installation and customization services at both shops. TX: 512-982-9393, CA: 562-981-6800.
If you are considering multiple items, contact us for shipping discounts. We install on premises at both locations.
CA Residents: 
WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov
Need Assistance?
We're here to help!
Call us at 512-982-9393 (Austin, TX) or
562-981-6800 (Signal Hill, CA)
and get assistance from one of our sales team members!
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