diff --git a/gestioncof/widgets.py b/gestioncof/widgets.py
index 758fc4ad..cbc9cd93 100644
--- a/gestioncof/widgets.py
+++ b/gestioncof/widgets.py
@@ -20,6 +20,7 @@ class TriStateCheckbox(Widget):
     def render(self, name, value, attrs=None, choices=()):
         if value is None:
             value = 'none'
-        final_attrs = self.build_attrs(attrs, value=value)
+        attrs['value'] = value
+        final_attrs = self.build_attrs(self.attrs, attrs)
         output = ["<span class=\"tristate\"%s></span>" % flatatt(final_attrs)]
         return mark_safe('\n'.join(output))