1. Introduction
The SanDisk 256GB Ultra microSDXC UHS-I Memory Card with Adapter is designed to provide reliable and high-performance storage for your compatible devices. This card is ideal for capturing and storing Full HD video and high-resolution photos, as well as for faster app performance on Android smartphones and tablets. Its robust design ensures durability in various conditions.

2. Setup
2.1 Inserting the microSD Card
- Identify the microSD slot: Locate the microSD card slot on your smartphone, tablet, MIL camera, or other compatible device. Refer to your device's user manual if you are unsure of the slot location.
- Orient the card: Hold the SanDisk microSDXC card with the gold contacts facing down (or as indicated by your device's manual) and the label facing up.
- Insert the card: Gently push the card into the slot until it clicks into place. Do not force the card, as this may damage it or your device.
2.2 Using the SD Adapter
The included SD adapter allows you to use your microSDXC card in devices that accept full-size SD cards, such as laptops, DSLR cameras, or SD card readers.
- Insert microSD into adapter: Slide the microSDXC card into the designated slot on the side of the SD adapter until it clicks securely.
- Insert adapter into device: Insert the SD adapter (with the microSD card inside) into the SD card slot of your compatible device.
- Lock/Unlock switch: The adapter features a small lock switch on its side. Slide it down to the 'Lock' position to prevent accidental data deletion or modification. Slide it up to 'Unlock' for writing data.

3. Operating the Memory Card
3.1 Storing Photos and Videos
Once inserted, your device should automatically detect the SanDisk Ultra microSDXC card as additional storage. You can then configure your device's camera settings to save photos and Full HD videos directly to the card. The 256GB capacity allows for many hours of Full HD video storage.
3.2 App Performance (A1 Rated)
This card is A1-rated, meaning it is optimized for faster app performance. When used with compatible Android smartphones and tablets, apps stored on the card will load and run more quickly, providing a smoother user experience.
3.3 Data Transfer
The SanDisk Ultra microSDXC card offers read speeds of up to 100MB/s, enabling quick transfer of files. For optimal transfer speeds, use a compatible USB 3.0 card reader when moving data to and from a computer.
4. Maintenance
The SanDisk Ultra microSDXC card is built for durability. It is:
- Waterproof: Designed to withstand immersion in water.
- Temperature Proof: Operates reliably in extreme temperatures.
- Shockproof: Resistant to impacts and drops.
- X-ray Proof: Protected against X-ray scanners, such as those found at airports.
Despite these features, it is recommended to handle the card with care, avoid excessive bending, and keep the contacts clean and free from debris.
5. Troubleshooting
5.1 Card Not Detected
- Reinsert the card: Remove the card and reinsert it firmly into the slot.
- Check compatibility: Ensure your device supports microSDXC cards of this capacity.
- Clean contacts: Gently clean the gold contacts on the card with a soft, dry cloth.
- Test with another device/adapter: Try the card in a different compatible device or with another SD adapter to rule out device-specific issues.
5.2 Slow Performance
- Check device specifications: Ensure your device supports UHS-I speeds for optimal performance.
- Format the card: If the card has been used extensively, reformatting it (after backing up data) can sometimes restore performance.
- Use a high-speed card reader: For transfers to a computer, use a USB 3.0 compatible card reader.
5.3 Data Corruption
- Safely Eject: Always safely eject the card from your device before physical removal.
- Avoid power loss: Do not remove the card or power off the device during read/write operations.
5.4 GoPro Battery Drain Issue
Some users have reported battery drain issues with GoPro cameras when using certain microSD cards. While the SanDisk Ultra is generally recommended, ensure your GoPro firmware is up-to-date and consider using a card specifically recommended by GoPro for your model if issues persist. The SanDisk Ultra microSDXC cards are known to be compatible and reliable for GoPro devices.
6. Specifications
| Feature | Detail |
|---|---|
| Brand | Sandisk |
| Model Name | Ultra |
| Item Model Number | SDSQUAR-256G-GN6MA |
| Memory Storage Capacity | 256 GB |
| Flash Memory Type | Micro SDXC |
| Hardware Interface | microSDXC |
| Read Speed | Up to 100 Megabytes Per Second |
| Secure Digital Association Speed Class | Class 10, U1, A1 |
| Special Features | Drop Proof, Temperature Proof, Water Proof, X Ray Proof |
| Product Dimensions | 0.59"L x 0.43"W |
| Item Weight | 0.16 ounces (4.54 Grams) |
| Compatible Devices | Camera, Smartphone, Tablet |
| UPC | 619659161972 |
7. Warranty & Support
7.1 Warranty Information
This SanDisk Ultra microSDXC Memory Card comes with a 10-year limited warranty. For full details on warranty terms and conditions, please refer to the official SanDisk website or contact customer support.
7.2 Customer Support
For additional support, product information, or to view other SanDisk products, please visit the official Sandisk Store.





