diff --git a/include/sua.hrl b/include/sua.hrl
index 94e5f98..cbbc113 100644
--- a/include/sua.hrl
+++ b/include/sua.hrl
@@ -119,7 +119,6 @@
 	 version	:: 0..255,
 	 msg_class	:: 0..255,
 	 msg_type	:: 0..255,
-	 msg_length	:: non_neg_integer(),
 	 payload
 	}).
 
diff --git a/src/sua_codec.erl b/src/sua_codec.erl
index 0365939..9e2e203 100644
--- a/src/sua_codec.erl
+++ b/src/sua_codec.erl
@@ -25,9 +25,10 @@
 
 parse_msg(DataBin) when is_binary(DataBin) ->
 	<<Version:8, _Reserved:8, MsgClass:8, MsgType:8, MsgLen:32/big, Remain/binary>> = DataBin,
+	RemainLen = MsgLen - 4,
 	OptList = parse_xua_opts(Remain),
 	#sua_msg{version = Version, msg_class = MsgClass, msg_type = MsgType,
-		 msg_length = MsgLen-4, payload = OptList};
+		 payload = OptList};
 parse_msg(Data) when is_list(Data) ->
 	parse_msg(list_to_binary(Data)).