# Serial Number in Custom Fields

[Custom fields](https://www.manageengine.com/network-monitoring/faq/custom-fields.html) in OpManager allow users to have additional information regarding the discovered device and acts as an inventory metadata to help in the management of your network better. The **serial number** in the custom field widget of a device is fetched by OpManager during the **add device**, **network discovery** and the **rediscovery** actions of SNMP devices. This serial number will be displayed under the custom fields section in the device snapshot page.

![Serial Number Inventory](https://www.manageengine.com/network-monitoring/kb/images/serial-number-custom-field.PNG)

You can also view this by adding the 'Serial Number' custom field as a column under **Inventory -> Devices** or fetch this as an inventory report.

![Serial Number Inventory](https://www.manageengine.com/network-monitoring/kb/images/inventory-serial-number.PNG)

To learn more on how to configure custom fields, [click here](https://www.manageengine.com/network-monitoring/help/custom-fields.html).

Listed below are the vendors that are currently supported by OpManager, for the automatic retrieval of the serial number of its devices.

- Cisco
- Dell
- Hewlett-Packard
- H3C
- Juniper
- CheckPoint
- Adtran
- 3Com
- Netscreen
- Palo Alto Networks
- Aruba Networks
- Extreme Networks
- Brocade
- Ceragon
- MiKroTik
- CIENA
- Ruckus
- ZD
- Alcatel-Lucent
- RuiJie
- Sophos
- Synology
- Fortinet
- Riverstone Networks
- American Power Conversion Corp.
- SonicWALL
- Mellanox
- Netgear
- Huawei
- Arista

For more assistance, please contact our support team at support@manageengine.com.