Man pages matching name nutscan_scan_eaton_serial in section 3:

nutscan_scan_eaton_serial.3.en	debian 10 / libupsclient-dev
nutscan_scan_eaton_serial.3.en	debian 11 / libnutscan-dev
nutscan_scan_eaton_serial.3.en	debian 12 / libnutscan-dev