Middle knob for adjusting the air vents to change wind direction.

Fits all W107 SL / SLC Models:

Model	Produced	Chassis designations	Chassis
280 SL	09/74 - 08/85	W107	107.042
280SLC	09/74 - 09/81	W107	107.022
300 SL	09/85 - 08/89	W107	107.041
350 SL	02/71 - 03/80	W107	107.043
350 SLC	02/72 -03/80	W107	107.023
380 SL	03/80 - 08/85	W107	107.045
380 SLC	05/80 - 09/81	W107	107.025
420 SL	09/85 - 08/89	W107	107.047
450 SL	03/73 - 11/80	W107	107.044
450 SLC	02/72 - 10/80	W107	107.024
500 SL	04/80 - 08/89	W107	107.046
500 SLC	03/80 -09/81	W107	107.026
560 SL	09/85 - 08/89	W107	107.048

Mercedes Benz reference number 1168330440.
OE-Quality: Original quality part (First Equipment Quality!)