This is the MSD-5, a small, hand-held shotgun-like device which has been suggested as an anti-drone weapon.
In recent weeks a number of Ukrainian social media accounts have shared the idea of using the MSD-5 as a short-range defence against diving FPV [first person view] drones.
the MSD-5 and is manufactured by Stellarium SV, a company based in Chernihiv, in northern Ukraine.
Sergey Flash (a Ukrainian serviceman and communication specialist) posted a video discussing the need for an immediate defence against FPVs and held up an MSD-5 describing it as “a possible way of protection”
Stellarium SV’s website explains that rather than being a weapon it is primarily sold as a signalling device with five different 12×88 cartridges available, two signalling cartridge types, a noise cartridge for scaring off animals, a cartridge which can extinguish flames and one for spraying plants to treat and protect them from various types of pests and diseases.
The device has 5 tubes or barrels and is electrically fired. It appears to have a cross bolt safety in front of the grip, below the exposed trigger. It weighs 800g and is powered by three CR123A batteries…
https://armourersbench.com/tag/stellarium-sv/
Armourer’s Bench Video: [4:37] https://youtu.be/vh3Z7OeWldI?si=