The serial number on the machine is located as follows:
AUTOMATIC X, ESSENTIAL G, and the ELECTRONIC 370 -
The underside of the power head.
FELIX Premium and Kombi - On side handle, underneath the stretch hose.
AIRBELT K - Under the carrying handle of the canister.
AIRBELT C - Underside of the tool compartment cover of the canister unit.
AIRBELT D - Underside of the canister unit.
POWER HEADS - ET-1, ET-2, ET-C, ET-H and the DISCO - The underside of the power head. Remove the polishing pad on the DISCO to see the serial number.
Note: There is no need to register the power head for the AIRBELT K and C canisters. However, if you purchase a power head as a stand alone item for central vacuuming or as a replacement power head, then you will need to register the serial number.