Clusters
Clusters are MongoDB Atlas for Government-managed MongoDB deployments. A cluster can be either a replica set or a sharded cluster.
Atlas for Government Considerations
When you create a project, you can designate it as an AWS GovCloud region-only project. If you do not, that project is an AWS Commercial region-only project. You may only deploy clusters to the type of region that your project supports.
AtlasGov clusters must be tier M20 or higher.
Atlas doesn't support Free and Flex clusters.
See the Atlas documentation to Configure Clusters.