SanDian (not to be confused with SanDisk) is a name that came up frequently while browsing though microSD cards on AliExpress. It’s very clear that they were attempting to trick buyers into thinking that they were SanDisk — offering a similar product lineup (Ultra, Extreme, Extreme PRO, etc.), using the same color scheme on their cards, and even copying the stylized “n” and “D” from the SanDisk logo. These cards failed the criteria that I set out for determining what’s considered a name-brand card; and given the similarities to SanDisk, I’ve categorized these as knockoffs.
AliExpress is usually pretty good about taking down knockoffs — but as of the time of this writing, they’re still available for sale (and even from the same seller that I originally purchased them from). I guess the differences are enough that AliExpress didn’t consider them to be knockoffs.
This card was — as I suspected when I bought it — fake flash. However, it ended up being a rather odd size, coming in at about 52.23GB.
In terms of performance: all performance measurements were below average, with the best single score coming in at just the 25th percentile. Random read speeds were 82.37 IOPS/sec — the single worst random read score of any card I’ve tested so far. However, keep in mind that — as of the time of this writing — these measurements are based on the results of a single card.
In terms of endurance:
- Sample #1’s first error was a series of data mismatch errors, affecting 16,454 sectors, during round 4. It has survived 2,816 read/write cycles in total so far.
- Samples #2 and #3 are still in the package, waiting to be tested.
October 19, 2025 (current number of read/write cycles updates automatically every hour)