diff --git a/source/blender/modifiers/intern/MOD_screw.c b/source/blender/modifiers/intern/MOD_screw.c
index 6642eecd33f..55fca7e8ecb 100644
--- a/source/blender/modifiers/intern/MOD_screw.c
+++ b/source/blender/modifiers/intern/MOD_screw.c
@@ -444,7 +444,7 @@ static Mesh *modifyMesh(ModifierData *md, const ModifierEvalContext *ctx, Mesh *
 
     /* Tag mvert as not loose. */
     BLI_BITMAP_ENABLE(vert_tag, med_orig->v1);
-    BLI_BITMAP_ENABLE(vert_tag, med_orig->v1);
+    BLI_BITMAP_ENABLE(vert_tag, med_orig->v2);
   }
 
   /* build polygon -> edge map */