You can display the revision level in SAP Engineering Control Center within the Object Browser.
Reading the Revision level is performance critical and is switched off therefore by default.
You can switch it on in <ECTR_INST>\customize\config\default.txt:
# Read and display the revision level of documents
# true: Read and display the revision level of documents
# false: Don't read and display the revision level of documents
plm.document.readRevisionLevel = true