Where can I find the serial number?

PROFITEST
Types: MBASE, MBASE+, MTECH, MTECH+, MPRO, MXTRA, INTRO, Edition

Switch on device - Rotary switch to Setup - SW-INFO button

SECUTEST
Types: BASE; BASE10, PRO
Rotary switch red to setup, switch to 3rd page, select system info

Types: S2N+, S2N+10, SIII+, 3PL, 3P, SIII+, SIII+H
Rotary switch to MENU - Setup, or directly to Setup, Service position

METRATESTER
Type: METRATESTER 5+3P
There is a sticker with 2 barcodes and 2 numbers on the top right above the mains connection. The lower number is the serial number

Type: METRATESTER 5+

MINITEST
Types: BASE, PRO, MASTER
There is a sticker with 2 numbers on the side with the mains connection above the fuses. The upper number F: is the serial number.

GEOHM C, METRISO C, PROFITEST C
There is a sticker with 2 barcodes and 2 numbers on the back of the device in the area of the mounting bracket. The lower number is the serial number.

PROFITEST 204+
There is a sticker with 2 barcodes and 2 numbers on the underside of the device. The lower number is the serial number. On older devices, the serial number is embossed into the plastic.
The sticker was later attached to the back of the appliance.

METRISO
Types: BASE, TECH, INTRO
There is a sticker with 2 barcodes and 2 numbers on the top right of the back of the device. The lower number is the serial number.

Types: XTRA
Switch on device - Rotary switch to Setup - SW-INFO button

SECULIFE
Types: SECULIFE IP
Switch on device - Rotary switch to Setup - SW-INFO button

Types: SECULIFE ST, ST+HV
Rotary switch to MENU - Setup, or directly to Setup, Service position