The trailed MLRS "Witcher" is based on a two-wheeled cart, which can be pulled by an SUV or pickup truck. Guides for 122 mm unguided rockets were probably removed from damaged multiple launch rocket systems BM-21 "Grad" that are in service with both Ukrainian and Russian troops.
Combat use of a miniature MLRS against the Russian occupation forces demonstrated by the Ukrainian territorial defense forces "AZOV" Dnipro.
This is not the first time that improvised MLRS have been used by the Ukrainian Defense Forces. However, usually guides from disabled BM-21 "Grad" and even from Russian helicopters shot down on the territory of Ukraine establish directly into a pickup truck, truck or mobile tripod.