diff --git a/src/Mod/Part/App/FeaturePartBox.h b/src/Mod/Part/App/FeaturePartBox.h
index 0349bb211..086fa40cd 100644
--- a/src/Mod/Part/App/FeaturePartBox.h
+++ b/src/Mod/Part/App/FeaturePartBox.h
@@ -32,7 +32,7 @@
 namespace Part
 {
 
-class Box :public Part::Primitive
+class PartExport Box :public Part::Primitive
 {
     PROPERTY_HEADER(Part::Box);