diff --git a/src/wireviz/wv_helper.py b/src/wireviz/wv_helper.py
index 13b660c9..72c14514 100644
--- a/src/wireviz/wv_helper.py
+++ b/src/wireviz/wv_helper.py
@@ -121,7 +121,7 @@ def open_file_write(filename):
 
 
 def manufacturer_info_field(manufacturer, mpn):
-    if manufacturer or mpn:
-        return f'{manufacturer if manufacturer else "MPN"}{": " + str(mpn) if mpn else ""}'
+    if manufacturer:
+        return f'{manufacturer}: {mpn}' if mpn else manufacturer
     else:
-        return None
+        return f'MPN: {mpn}' if mpn else None