Samsung Galaxy S21 5G G991U AT&T 128GB Phantom Gray Grade A+
An AT&T-locked Android smartphone with a 6.2-inch Dynamic AMOLED display, Snapdragon 888 processor, 128GB storage, and a 64MP telephoto camera capable of 8K video recording
- Storage drive128 GB
- Operating systemAndroid
- Form factorBar Phones
- Main screen size6.2 in (15.7 cm)
- Product typeCell Phone
- Product colorGray
- Snapdragon 888 powers smooth multitasking and 5G speed
- 2-inch Dynamic AMOLED 120Hz display shows vivid detail
- Triple camera with 64MP telephoto captures 8K video
- 128GB storage plus 8GB RAM holds apps and media
- 4000mAh battery lasts through a full day
AT&T-locked Galaxy S21 5G
The Samsung Galaxy S21 5G model G991U is an AT&T-only smartphone sold new with 128GB of storage in Phantom Gray. It runs Android 12 with One UI on a Snapdragon 888 processor and 8GB of RAM. The 6.2-inch Dynamic AMOLED display supports HDR and a 120Hz adaptive refresh rate behind Gorilla Glass Victus.
Carrier lock and storage ceiling
This unit works exclusively on the AT&T network, so it cannot be activated on other carriers without an unlock request. Internal storage is fixed at 128GB with no microSD expansion slot, limiting space for 8K video files and large apps. The 4000mAh battery is not user-replaceable.
Ready to use with included charger
A UL-approved power adapter and cable are supplied, so the phone charges immediately without extra purchases. Original packaging, headphones, SIM card and manual are absent; a SIM must be sourced from AT&T. The device passed a 30-point inspection and carries a 90-day warranty.
How it compares
Measured against everything we stock in No-Contract Smartphones, at today’s prices. Recalculated every night.
- Price $130.99
- Cheaper than about 70% of the 646 comparable items (median $180.49).
- Storage drive 128 GB
- Typical for this category: the median of 506 items is 128 GB.
Specifications
| Product | |
|---|---|
| Brand name | Samsung |
| Product line | Galaxy S21 5G |
| Model name | G991U |
| Product type | Cell Phone |
| Product color | Gray |
| Storage | |
| Storage drive | 128 GB |
| Display | |
| Touchscreen | Yes |
| Main screen size | 6.2 in (15.7 cm) |
| Connectivity | |
| Built-in GPS | Yes |
| Size & build | |
| Form factor | Bar Phones |
| Software | |
| Operating system | Android |
Questions about this item
Should I pick the 128 GB or 256 GB version of the Galaxy S21 5G?
The 128 GB model stores plenty of apps, photos and 8K clips; choose 256 GB only if you keep large media libraries offline.
What does the Snapdragon 888 actually deliver in daily use?
The 888 chipset drives the 120 Hz display, 8K video capture and 5G speeds without lag.
Which network standard does the G991U support and what speed ceiling does it hit?
The AT&T-locked G991U connects to 5G networks for multi-gigabit downloads where coverage exists.
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