via this auction

This compact sound module is loaded with features and can bridge between a variety of inputs.
It's rare to find a BRAND NEW and UNOPENED model and this item has the original batteries, as well as the manual and documentation.
The sound is distinctive with a crisp tone that stands strong in the mix.
I think Florian Pilz is correct when he suggests this synth might be the new 303 [3rd Bad Gear video here], but that probably depends on your appreciation for that famous mono-synth.
The A-01 has a lot of variety, from softer organ-like tones through to crucnhy percussive and bit-crushed basses.
Roland's website provides the following details:
Ultra-compact controller and sound generator
Highly portable for mobile music making
High-quality construction with metal front panel
Dual assignable ribbon controls for pitch bend, modulation, sound preview, CC, and more
MIDI over Bluetooth®
CV/GATE outputs for legacy analog/modular synthesizers
Battery-operated (4 x AA) or USB bus-powered
192x40 graphic LCD screen
Built-in 0.5 W mini-speaker for real-time sounds"