SLK Spring pads:

Front
A 210 321 01 84 (5mm)
A 210 321 02 84 (9mm)
A 210 321 03 84 (13mm)
A 210 321 04 84 (17mm)
A 210 321 05 84 (21mm)

Rear
A 210 325 01 84 (5mm)
A 210 325 02 84 (9mm)
A 210 325 03 84 (13mm)
A 210 325 04 84 (17mm)

Basically you can adjust the height of your car with different pads. Sometime mercedes use this to adjust the camber.