Advan S4X
Advan S4X is a Advan firmware file listed under Advan, distributed as Advan_S4X_V2.1_SPD.zip with a download size of 401 MB. It is built for Unisoc (Spreadtrum)-based devices. It is flashed with SPD ResearchDownload (or UpgradeDownload). It was published on June 16, 2026. This page has been viewed 8 times. It is available to download free of charge. Before flashing, verify the file matches your exact device model and back up your data.
About Advan S4X
Looking for the official stock firmware for your Advan S4X? You're in the right place. Below is the original Advan flash file you need to restore your device, whether you're fixing a software issue or starting fresh. Flashing the stock ROM can clear boot loops, failed updates, a frozen logo screen, or sluggish performance, replacing the system software with a known good copy. File Name: Advan_S4X_V2.1_SPD.zip File Size: 401 MB Before flashing, back up your data (the process wipes the device), charge above 50 percent, and install the correct USB drivers on your computer. Once installed, your Advan S4X should boot up like new. Use the right file for your exact model and don't interrupt the process.
File Details
| File name | Advan S4X |
|---|---|
| Package | Advan_S4X_V2.1_SPD.zip |
| Brand / Platform | Advan |
| Category | Advan |
| Platform | Unisoc (Spreadtrum) |
| Flash tool | SPD ResearchDownload (or UpgradeDownload) |
| Package format | ZIP archive |
| File size | 401 MB |
| Date added | June 16, 2026 |
| Price | Free |
How to flash Advan S4X with SPD ResearchDownload
- Confirm Advan S4X matches your exact device model and that it is intended for Advan hardware.
- Back up your personal data, as flashing firmware can erase the device. Charge the battery above 50%.
- Download the file (401 MB) using the button above and extract it on a Windows PC.
- Install the SPD / Unisoc USB drivers, then open SPD ResearchDownload (or UpgradeDownload).
- In the tool, load the .pac firmware file from the extracted folder.
- Start the flash, then press Start in the tool, then connect the powered-off phone while holding Volume Down (boot key).
- Wait for the success message before disconnecting. Leave "Erase NV" unticked unless you intend to wipe IMEI and calibration data.
Guides for this firmware
- Flashing .pac Files with SPD ResearchDownload GuideSPD ResearchDownload (also known as UpgradeDownload) is a specialized flashing tool used to install stock firmware on devices powered by Unisoc (Spreadtrum) chipsets. It is primarily used to unbrick…
- How to Use SPD ResearchDownload: Firmware Flashing GuideSPD ResearchDownload (also known as UpgradeDownload) is a specialized flashing tool used to install stock firmware on devices powered by Unisoc (Spreadtrum) chipsets. It allows technicians and users…
Frequently asked questions
Is Advan S4X free to download?
Yes, Advan S4X can be downloaded free of charge from this page.
How large is the download?
The Advan S4X package is 401 MB.
Which tool do I need to flash Advan S4X?
Advan S4X is Unisoc (Spreadtrum) firmware, so it is flashed with SPD ResearchDownload (or UpgradeDownload) using the .pac firmware file.
Which devices is this firmware for?
This file is intended for Advan devices. Always confirm it matches your specific model before flashing.