Honda EU20i Owner's Manual page 33

Never connect the different generator models and types.
Never connect a cable other than the receptacle box for parallel
operation.
Connect and remove the receptacle box for parallel operation with
the engine stopped.
For single operation, the receptacle box for parallel operation must
be removed.
1. Install the receptacle box for parallel operation on to the one
generator and secure it with setting band as shown.
Set the belt on the front side of the handle.
Secure the narrow belt to the handle with the velcro fastening.
Pass the upper wide belt through the lower belt hook and secure
with the velcro fastening.
Route the receptacle box wires under the engine switch.
Install the belts so they are not slack.
NARROW BELT
VELCRO FASTENING
RECEPTACLE BOX FOR
PARALLEL OPERATION
HANDLE WIDE BELT VELCRO FASTENING
LOWER BELT HOOK
ENGINE SWITCH
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