How to update field properties with Model Builder

[JoseSanchez]

Helo everyone,

How can I update the property "Allow NULL values" of a field with Model builder?

I need to change this property several feature classes from No to Yes.

Thank you

[FreddieGibson]

Use the Alter Field (Data Management) tool

​Alter Field

http://desktop.arcgis.com/en/desktop/latest/tools/data-management-toolbox/alter-field-properties.htm