An interesting gun. It can self propel albeit slowly under it's own power, which is a Volkswagen engine attached to a hydraulic pump and the wheels attached to hydraulic motors. It has two large wheels on back and two smaller wheels forward. The driver stands on back and appears to control it and to steer using hydraulic leavers.
The ones they are giving to Ukraine are not all their 155mm guns, just all of their old phased out ones. They have a number of new tracked self propelled Korean guns they bought to replace these 45 year old ones they phased out around two years ago.