diff --git a/src/TensorFlowNET.Core/Keras/ArgsDefinition/Rnn/GRUOptionalArgs.cs b/src/TensorFlowNET.Core/Keras/ArgsDefinition/Rnn/GRUOptionalArgs.cs
index d441dc82..1d215576 100644
--- a/src/TensorFlowNET.Core/Keras/ArgsDefinition/Rnn/GRUOptionalArgs.cs
+++ b/src/TensorFlowNET.Core/Keras/ArgsDefinition/Rnn/GRUOptionalArgs.cs
@@ -4,10 +4,8 @@ using System.Text;
 
 namespace Tensorflow.Keras.ArgsDefinition
 {
-    public class GRUOptionalArgs
+    public class GRUOptionalArgs : RnnOptionalArgs
     {
         public string Identifier => "GRU";
-
-        public Tensor Mask { get; set; } = null;
     }
 }
diff --git a/src/TensorFlowNET.Core/Keras/ArgsDefinition/Rnn/LSTMOptionalArgs.cs b/src/TensorFlowNET.Core/Keras/ArgsDefinition/Rnn/LSTMOptionalArgs.cs
new file mode 100644
index 00000000..2829927c
--- /dev/null
+++ b/src/TensorFlowNET.Core/Keras/ArgsDefinition/Rnn/LSTMOptionalArgs.cs
@@ -0,0 +1,11 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Tensorflow.Keras.ArgsDefinition.Rnn
+{
+    public class LSTMOptionalArgs : RnnOptionalArgs
+    {
+        public string Identifier => "LSTM";
+    }
+}
diff --git a/src/TensorFlowNET.Core/Keras/ArgsDefinition/Rnn/SimpleRNNOptionalArgs.cs b/src/TensorFlowNET.Core/Keras/ArgsDefinition/Rnn/SimpleRNNOptionalArgs.cs
new file mode 100644
index 00000000..a8b8caf0
--- /dev/null
+++ b/src/TensorFlowNET.Core/Keras/ArgsDefinition/Rnn/SimpleRNNOptionalArgs.cs
@@ -0,0 +1,11 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+
+namespace Tensorflow.Keras.ArgsDefinition.Rnn
+{
+    public class SimpleRNNOptionalArgs : RnnOptionalArgs
+    {
+        public string Identifier => "SimpleRNN";
+    }
+}