Somu is a tiny FIDO2 security key you can use with your Google, Twitter, and GitHub accounts for two-factor authentication, or your Microsoft account for passwordless login. Somu fits in your USB port, so you'll never forget your key again.

Somu is the micro version of Solo. We were inspired to make a secure Tomu, so we took its tiny form factor, we added the secure microcontroller and firmware of Solo, et voilà! Here we have Somu.

Specifications:

Supported Protocols : FIDO2, U2F
Supported Operating Systems: Linux, Microsoft Windows, Mac OS X, Chrome OS
Supported Browsers: Chrome, Firefox, Edge, and Safari support is coming soon (GA in MacOS Catalina)
Secure Processor: STM32L432KC (with TRNG, security isolation for keys, two levels of locked flash)
Crypto Algorithms: ECC P256 (as per FIDO2 standard)
Host Interface: USB-A
Interaction: two touch buttons - in our FIDO2 firmware the two buttons behave as a single one
Feedback: RGB LED
Size: 0.5 x 0.5 x 0.1 inches (13 x 13 x 2.4 mm)
Weight: 0.11 ounces (3 g)

Comparisons:

	Somu	Tomu	Yubikey Nano 5	Yubikey Nano 4	Solo
Tiny	Yes	Yes	Yes	Yes	No
Secure*	Yes	No	Yes	Yes	Yes
Open Source	Yes	Yes	No	No	Yes
U2F	Yes	Yes	Yes	Yes	Yes
FIDO2	Yes	No	Yes	No	Yes
Buttons	2	2	1	1	1
LEDs	RGB	R+G	RGB	RGB	RGB
Made in	Italy	China	US / Sweden	US / Sweden	Italy
Retail Price	$35	$30	$50	n/a	$20

* The microcontroller supports security features to protect against physical extraction of key material

The PCB is a one mm thick two-layer board, with Z-axis milling. The milling makes the short tabs on the sides allow the PCB to "slide fit" into the case.

The edge that protrudes (slightly) out of your USB port is plated to make two independent capacitive touch buttons. Firmware will currently combine and treat them as one, but they may be configured for two different actions in the future.