diff --git a/BIN/DU.S.TXT b/BIN/DU.S.TXT
index fb876a53..ae8846b1 100644
--- a/BIN/DU.S.TXT
+++ b/BIN/DU.S.TXT
@@ -411,7 +411,7 @@ CS.END
 OptionList          .AS "SAsa"
 OptionVars          .DA #bSummary,#bAllFiles,#bSummary,#bAllFiles
 *--------------------------------------
-MSG.USAGE           .AS "Usage : DU\r\n"
+MSG.USAGE           .AS "Usage : DU [-A] [-S] [filespec]\r\n"
                     .AS "   -A : Show all files (not only directories)\r\n"
                     .AZ "   -S : Show only summary\r\n"
 MSG.REG1            .AZ "%5D  "