diff --git a/src/transport.rs b/src/transport.rs
index 346e1a722..97a23dbd8 100644
--- a/src/transport.rs
+++ b/src/transport.rs
@@ -30,7 +30,7 @@ pub(crate) enum ConnectionSecurity {
     /// Implicit TLS.
     Tls,
 
-    // STARTTLS.
+    /// STARTTLS.
     Starttls,
 
     /// Plaintext.