datAshur SD is an ultra-secure PIN authenticated USB flash drive with removable microSD storage [Review]

Although a lot of people and companies now choose to store their data in the cloud, where it can be accessed from anywhere, USB flash drives remain popular. But what happens if you lose a drive or it gets stolen? All of your personal data could be at risk.

You could secure your data using software, or better yet a hardware solution like the datAshur PRO, from iStorage which protects your files with military grade XTS-AES 256-bit encryption. The problem, of course, with a flash drive is it has a fixed -- and possibly limited -- capacity. Not so the datAshur SD, reviewed here, as this uses microSD cards for storage. If you run out of space, you can take out the full card and drop in a new one.

Now, you’re probably thinking what’s to stop someone removing the microSD card and viewing its contents, and the answer is they only work in the datAshur SD drive.

You can’t use just any microSD card unfortunately, as only genuine iStorage microSD cards are compatible. They are a bit more expensive, but not ridiculously so, and come in a range of capacities from 32GB -- 1TB. I tested the drive with a 512GB card.

The datAshur SD itself is 87.2mm x 19.9mm x 13.5mm (H,W,D), which is longer than most flash drives, but that’s because it has an alphanumeric keypad built in.

The datAshur SD has a USB-C connector, but it comes with a USB-C to USB-A adapter so you can use it with older hardware. That does look a little odd when clicked into place, and adds 35mm to the overall length, but it works well and that’s the main thing.

The drive also comes with an extruded aluminum sleeve to protect against accidental button presses in your pocket.

datAshur SD is epoxy coated, to protect it against any physical attacks, and dust and water resistant (IP68 certified). The keyboard is wear resistant, so if you’ve chosen to lock the drive using a memorable word (rather than just a number sequence) you shouldn’t have to worry about the letters rubbing off. A solid loop on the end of the drive lets you attach it to a keyring or bag.

To get started, you just place the card in the slot on the side of the drive and press it in until it clicks into place. iStorage recommends you charge the drive for 20-30 minutes before using it by plugging it into a powered port.

It comes in 'Initial Shipment State' and unlike some similar drives doesn’t have a pre-set admin PIN so you’ll need to create this. The PIN can be between 8 and 64 digits long. Yes, you can have a 64 digit PIN if required. This PIN can’t contain all sequential numbers (so no 12345678 or 98765432) or all repeating numbers (so that’s no 11111111 or 22222222). It’s important to remember the PIN you create as there’s no recovering it if forgotten.

Creating an admin PIN is just a matter of inserting the microSD card and then pressing and holding the shift key on the drive for one second. The red and green LEDs will become solid at which point you’ll need to press and hold the Key and 1 buttons. When you see blinking green and solid blue LEDs, enter your PIN and press the Key button. You’ll see blinking green and solid blue again. Re-enter the PIN and press the Key button. Plug the drive into a spare USB port.

You’ll now need to format the microSD card in Windows or macOS. (datAshur SD is OS and platform independent, so you can use it on pretty much any device with a USB port.)

Should you be worried about losing the drive and/or microSD card, the iStorage datAshur SD KeyWriter software lets you clone a drive with the same encryption key so you can make a handy backup. You get a free license for this when purchasing a twin pack.

There are read-only and bootable modes available, it supports both user and admin PINs, and there’s a brute force self-destruct feature that kicks in after ten unsuccessful attempts to guess the PIN. What’s particularly interesting about this feature is unless you’ve cloned another datAsure SD as a backup drive, data on other microSD cards encrypted by the drive you’ve self-destructed will also be inaccessible, and therefore lost forever.

If you’re worried about losing data through forgetfulness of user error, you can create a one-time user recovery PIN (this can be deleted when no longer needed).

You don’t have to remember to lock the drive once you’ve finished using it -- unplugging it does the job for you. If you unlock the drive, and don’t plug it into a port, it will lock automatically after a brief period.

Having used the datAshur SD for the past few weeks I can definitely recommend it, especially if you work for a company where secure sharing of data is commonplace.

datAshur SD is priced from £69/$82. Compatible microSD cards cost from £25/$30 (32GB) up to £300/$358 (1TB). You can buy both drive and cards direct from here.