SanDisk Ultra is a brand of Western Digital which is the same company that sells external hard-disk storage devices under the brand WD Elements and WD Portable.

STORAGE FORMAT: Since the previous FAT32 version had a limitation of file transfer size of a maximum of 4 GB for a single file & NTFS was not compatible with mac OS so with increasing file sizes ex FAT format was devised which doesn’t have a size limitation like FAT yet is compatible with Mac as well. So our drive has only ex FAT & NTFS formats to choose & comes in ex FAT by default with 128 KB file allocation size. Increasing the file allocation size may increase the transfer speeds a little but will affect the storage capacity little too. Changing it from 128 to 256 KB increased my write speeds from 13 MB/s to 15 MB/s if that’s a relief to anyone. Blazing transfer speeds lets you offload cards fast. Use with the SanDisk® MobileMate® USB 3.0 microSD™ card reader 6 to achieve up to 150MB/s speeds 2. Finally with every passing minute it became all the more unbearable and annoying. Even in NTFS format speeds were the same.FILE SYSTEM FORMATTING THE PEN DRIVE: Unless you are sure you won't use your pen drive on a particular device, don't format the pen drive to change its FAT32 File System.

TOO TIGHT FOR PHONES: The pen drive is a tight fit on mobile phones & tablets - so be careful when pulling it out so as to not damage your phone - because this is also the charging point for your phone. If you feel that your phone is too tight for this pen drive, then it is best not to use it for phone data storage management. Full HD (1920x1080) video support may vary based upon host device, file attributes, and other factors. See: www.westerndigital.com/brand/sandisk/hd-video-definitions. A Note : Speed enthusiasts though should refrain from this version & should try its designated speedier extreme versions or other brands like transcend, Samsung.STORAGE : Out of the total name plate rating of 64 GB , the actual allocated space for usage is around 57 GB which is ok enough. My basic intent was to load bulk movies from my laptop into it and watch it over my TV or mobile, However when I was transferring 6 movies of a total size 8.1 GB , it started showing 15 minutes which kept on getting higher & it felt like waiting forever for it to happen.

SanDisk is an Israeli-American manufacturer of flash memory products, including memory cards and readers, USB flash drives, and solid state drives. As of February 2015, it is the third-largest manufacturer of flash memory. WARRANTY : The product comes with a 5 year limited warranty which is one of the segment best offers. Approximations: Results and Full HD (1920x1080) video support may vary based on host device, file attributes, and other factors. SPEED: The Speed is extremely good for Windows OS laptop, Linux OS laptop and Android Mobile Phones.It takes Forever - to transfer anything. Maybe I - misunderstood "Ultra" or somebody missed "Ultra-Slow" in the model tag line. The device comes with the title “SanDisk Ultra - Dual Drive m3.0” and is the newer 2017 version of its previous iteration. Here I need to quote that the term “Ultra” came quite as a surprise to me as I found nothing in lines with a common understanding of Ultra. We will discuss it in detail in upcoming columns of speed. Benchmark Crystal Disk mark scores for a file transfer of 500 MB size were 34 MB/s -Read & 19 MB/s – write which looked like a mere consolation. Transfer between my Samsung S7 mobile & S2 tablet too was not fast. But For Example, If you have decided that you won't use it on mobile phones or tablets because the fitting is too tight and you don't want to risk damage to this point which is primarily used for charging - then go ahead and format the pen drive for your laptop. With a micro-USB connector on one end and a USB 3.0 connector on the other, the drive lets you move content easily between your android phones, tablets (with micro USB ports only) or laptops.

See Western Digital White Paper- Flash 101 and Flash Management. A detailed overview of flash and flash management (August 2018): documents.westerndigital.com/content/dam/doc-library/en_us/assets/public/western-digital/collateral/white-paper/white-paper-sandisk-flash101-management.pdf SAME AS OTHERS: For the 64GB pen drive, actual storage space available is 57.2GB. This is normal and not some fraud or fake advertisement. This is because it has FAT32 File System. Also, the device uses some space for its functionality and use.if like most people you will be using this pen drive on laptops or other devices of friends or co-workers, then leave the existing FAT32 File System as it is.