An old WW2 era American M4 'High Speed' Tractor named 'Schermon', used originally for towing artillery guns converted into a technical used for troop transport and also fire support, as a 20MM cannon was fitted to the rear tray. The vehicle was originally used during WW2 by the Yugoslavian armed forces, who after WW2 sold it to a civilian logging company, where it was used in heavily wooded areas as a tree hauler before it was lost during the post-war period. 

 

It was re-discovered in the forest near Sisak, Central Croatia during the summer of 1991, where it was hauled out of the woods despite it's bad condition and re-built into a technical by the company Sisački Autopromet, who repaired the vehicle and added a new interior, the added armour and weapons, and modified the engine so it was back in working condition. The weird appearance for the engine and exhaust was because the armoured shell was already being prepared before the engine was, so they just cut holes in it to allow the exhaust to vent outside rather than inside the troop compartment to prevent the passengers asphyxiating from the engine fumes.