Picture 1: Type MM17 in command field and press Enter or click MM17 in SAP menu: Logistics / Materials Management / Material Master / Material / MM17 - Mass Maintenance.
Picture 2: Select table name (MARA for general material data) and press Execute or F8.
Picture 3: Click Data Records to be Changed tab and choose materials using multiple selection.
Picture 4: Click Execute or F8.
Picture 5: Click Select fields icon and select the field(s) you want to change (Base unit of Measure in this example).
Picture 6: Base Unit of Measure is displayed.
Picture 7: Insert new Base Unit of Measure in New Values field and click Carry Out a Mass Change icon.
Picture 8: New Base Unit of Measure is displayed. Click Test Changes icon or Crtl+Shift+F7.
Picture 9: Test is successful. Back
Picture 10: Click Save icon or Ctrl+S.
Picture 11: Change is successful.
Picture 12: Verification in MARA table.