diff --git a/gtk/gtkmagnifier.c b/gtk/gtkmagnifier.c
index af06d213d3..5b5b6ab7ac 100644
--- a/gtk/gtkmagnifier.c
+++ b/gtk/gtkmagnifier.c
@@ -202,6 +202,8 @@ gtk_magnifier_class_init (GtkMagnifierClass *klass)
                                                          P_("resize"),
                                                          FALSE,
                                                          G_PARAM_READWRITE));
+
+  gtk_widget_class_set_css_name (widget_class, "magnifier");
 }
 
 static void