Loaded calipers are one that include brake pads. The decision you need to make is whether your car has ATe or Bendix calipers as it was built. MB suggest not interchanging them. Ate calipers will have the ATe logo on them "ATe", some Bendix calipers also say Bendix on them but not all.

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician