Edge with Bar Support structure
The Edge with Bar Support 
tool creates a secondary type of additive support structure intended to be used with a Bar Support.
The bar supports are vertical rods between the part and the build platform, or between two surfaces on the same part. The supports are placed at downward-facing edges where typical bar supports would not get generated.
Note: This feature is available only when you select a machine with additive MPBF or SLA/DLP capabilities.