According to PET cars without an O2 sensor have option code M150 (Operation with leaded gas). Looking these up results in to following:
Code # Note
C00 2 German specification
C06 3 French colonial specification
C16 1 UK specification
C24 18 New Zealand specification
C26 33 South African specification
C31 8 Saudi Arabian specification
C32 31 Arab Gulf State specification
C99 21 Non standard specification
Anyone who knows the exact differences? I've seen a plug for the O2 sensor and a potentiometer. I cannot find an exhaust without a cat in PET...