diff --git a/base_logic/lib/boxes.v b/base_logic/lib/boxes.v
index 6079a03e4943b601e48d54ba6e52007e5045ccf0..820a79e2dbfd8a737826ebce511c04abc1855e91 100644
--- a/base_logic/lib/boxes.v
+++ b/base_logic/lib/boxes.v
@@ -197,4 +197,4 @@ Proof.
 Qed.
 End box.
 
-Typeclasses Opaque slice_name slice box.
+Typeclasses Opaque slice box.