The 4th gen Aurora A3 has a USB-C port, metal switch, magnetic two-way clip, and a better user interface, etc. All these upgrades are based on the fact that the size keeps the same. It's still in a small keychain size with a powerful output.
Its length is 57.5mm and diameter is 15.6mm, weighs only 23.1g.
The upgraded metal switch gets clicking more comfortable and strong feedback. Regarding the user interface, it has a lockout mode and keeps the momentary-on feature.