A Flush Fitting Hard Cover Built For Silverado And Sierra Crews Who Haul For A Living
This hard folding tonneau cover is engineered for 2019 to 2020 Chevrolet Silverado 1500 and GMC Sierra 1500 trucks with a 6.5 ft bed. A premium grade matte black aluminum surface sits over a high density polymer core, giving the panels the strength to handle heavy-duty use without adding bulk. The low profile design rests nearly flush with the bed rails for a clean factory look while still supporting up to 400 lbs of evenly distributed weight.
Key Features
- Matte black aluminum top panels with a high density polymer core
- Patented rail and clamp system with automatic slam latches on every panel
- Tip and Click no-drill mounting system installs in under 30 minutes
- Padded soft-impact underside protects cargo and looks finished from below
- Upgraded seals and tight-fit clamps block water, dust, and debris
- Folds fully to the cab for 100 percent bed access while driving
- Tested from negative 40 to 180 degrees Fahrenheit and up to 95 percent humidity
- Backed by a 5-year manufacturer warranty
Fitment Table
| Year Range |
Make |
Model |
Trim |
| 2019-2020 |
Chevrolet |
Silverado 1500 |
Custom |
| 2019-2020 |
Chevrolet |
Silverado 1500 |
Custom Trail Boss |
| 2019-2020 |
Chevrolet |
Silverado 1500 |
High Country |
| 2019-2020 |
Chevrolet |
Silverado 1500 |
LT |
| 2019-2020 |
Chevrolet |
Silverado 1500 |
LT Trail Boss |
| 2019-2020 |
Chevrolet |
Silverado 1500 |
LTZ |
| 2019-2020 |
Chevrolet |
Silverado 1500 |
RST |
| 2019-2020 |
GMC |
Sierra 1500 |
AT4 |
| 2019-2020 |
GMC |
Sierra 1500 |
Denali |
| 2019-2020 |
GMC |
Sierra 1500 |
Elevation |
| 2019-2020 |
GMC |
Sierra 1500 |
SLE |
| 2019-2020 |
GMC |
Sierra 1500 |
SLT |
Specifications
| Detail |
Value |
| Manufacturer Part Number (MPN) |
UX12023 |
| UPC |
Not publicly listed by manufacturer |
| Brand |
UnderCover |
| Series |
Ultra Flex |
| Bed Length |
6.5 ft (6'6") |
| Finish |
Matte Black |
| Material |
Aluminum with high density polymer core |
| Weight Capacity |
400 lbs evenly distributed |
| Installation |
No-drill clamp on, under 30 minutes |
| Warranty |
5-year limited |
| Country of Assembly |
Made in the USA |
What's Included
- Hard folding cover panels
- Pre-assembled mounting side rails
- Mounting clamps and hardware
- Bulkhead adhesive seal
- Drain tubes
- Installation instructions
About UnderCover
UnderCover designs and builds hard folding, retractable, and one-piece tonneau covers for full-size trucks in the United States. The brand focuses on flush-fitting panel systems, no-drill installation, and weather sealing that holds up to daily work truck use, backing its Ultra Flex line with a 5-year warranty.
FAQ
What is the UX12023?
The UX12023 is an UnderCover Ultra Flex hard folding tonneau cover built for 2019-2020 Chevrolet Silverado 1500 and GMC Sierra 1500 trucks with a 6.5 ft bed. It features a matte black aluminum top, a high density polymer core, and a no-drill clamp-on mounting system. This is the direct manufacturer part number for this application.
Does this cover work with the MultiPro or Multi-Flex tailgate?
Yes, this Ultra Flex cover is designed to work with or without the factory MultiPro and Multi-Flex tailgate on compatible Silverado and Sierra trucks.
Will this cover fit a truck with a factory bed storage box?
No, this cover will not work with factory bed storage boxes since the mounting rails need a clear, uninterrupted bed rail surface.
How much weight can this Ultra Flex cover hold?
It supports up to 400 lbs when the load is evenly distributed across the closed panels.
Is drilling required to install this cover?
No, the Tip and Click mounting system clamps onto the factory bed rails and typically installs in under 30 minutes without drilling into the truck bed.
Is the UX12023 made specifically for the 6.5 ft bed?
Yes, the UX12023 is engineered to match the 6.5 ft bed dimensions on 2019-2020 Silverado 1500 and Sierra 1500 trucks, so panel alignment and rail fitment are precise for this bed length only.
Can I still access the full bed with the cover installed?
Yes, the panels fold forward to the cab and lock in place, giving full bed access while still allowing the truck to be driven safely with the cover open.
What kind of weather protection does this cover offer?
The cover uses upgraded seals and tight-fit clamps designed to keep out water, dust, and debris, and it has been tested from negative 40 to 180 degrees Fahrenheit.
What warranty comes with the UX12023?
UnderCover backs the Ultra Flex UX12023 with a 5-year limited warranty against manufacturing defects.
Install Instructions
- Clean the bulkhead surface behind the cab with isopropyl alcohol before applying any seals
- Apply the bulkhead adhesive seal and trim to fit
- Install the pre-assembled side rails onto the bed rails and secure with the included clamps
- Attach the drain tubes to the fittings at the front of each side rail and route them out of the bed
- Set the folded cover onto the mounting rails with the smallest panel toward the cab
- Center the cover side to side and front to back on the bed rails
- Tighten the retaining clamps on both sides to lock the cover to the rails
- Test the slam latches by folding the panels open and closed to confirm secure operation
