Attach tools is used to manage referenced models and select reference tools.

You can access this dialog from the following:

Ribbon: Home > Primary > Attach Tools Dialog

Setting	Description
References	Allows you to manage reference attachments using the References dialog.
Raster Manager	Allows you to manage raster reference attachments using the Raster Manager dialog.
Point Clouds	Allows you to import, control, visualize and manipulate point cloud images using the Point Clouds dialog.
Reality Mesh	Allows you to attach and manipulate reality meshes using the Reality Mesh Attachments dialog.
Attach iTwin	Allows you to attach an iModel as a reference in a DGN. Note: Attach iTwin option is enabled only when the active DGN is associated with a WorkSet and a ProjectWise Project.

Attach Tools Dialog