diff --git a/csharp/Sinexcel 12K TL/DataType/SinexcelWeekDays.cs b/csharp/Sinexcel 12K TL/DataType/SinexcelWeekDays.cs
new file mode 100644
index 000000000..5882c86ae
--- /dev/null
+++ b/csharp/Sinexcel 12K TL/DataType/SinexcelWeekDays.cs	
@@ -0,0 +1,14 @@
+namespace InnovEnergy.Lib.Devices.Sinexcel_12K_TL.DataType;
+
+public enum SinexcelWeekDays : byte
+{
+    None     = 0b00000000,
+    Sunday   = 0b00000001,
+    Monday   = 0b00000010,
+    Tuesday  = 0b00000100,
+    Wednesday= 0b00001000,
+    Thursday = 0b00010000,
+    Friday   = 0b00100000,
+    Saturday = 0b01000000,
+    All      = 0b01111111
+}
\ No newline at end of file