they all are not slot cars (as you wrote) but supering with:
- on-rough tire treads
- matted tire sidewalls
- detailed interiors
- flexible air tubes
- cables inside
- roll cage paddings with tapes
- painted seats
- scratchbuild flexible window nets
- painted drivers (tin)
- paintbrushed inner floors
- all glases with black painted shaded areas
- grey standard frames or other colors of some teams
- clear varnished decals
- paintbrushed bottoms
- on drilled exhaust pipes
- grills made by nets
- radio antennas
