I should have pointed out that was from the ref

DB<3> x $_->summary
0  DatastoreSummary=HASH(0x9afa1b0)
   'accessible' => 1
   'capacity' => 12884901888
   'datastore' => ManagedObjectReference=HASH(0x9b050a8)
      'type' => 'Datastore'
      'value' => 'datastore-81'
   'freeSpace' => 7937720320
   'multipleHostAccess' => 0
   'name' => 'Boot_esx03d'
   'type' => 'VMFS'
   'url' => 'sanfs://vmfs_uuid:4d100997-16f1d4cc-20aa-00145ea7f14a/'