Precor EFX 447 Owner's Manual page 12

The equipment serial number is located on the rear
stabilizer bar, just below the power switch.
Figure 1: EFX serial number label position
Important Safety Instructions
The console serial number is located inside the USB
connector compartment on the back of the console.
You will need to open the cover of this compartment to
see the number.
Figure 2: Console serial number label position
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