diff --git a/DiscImageChef.Devices/ChangeLog b/DiscImageChef.Devices/ChangeLog
index 68b05a705..eb6713f6d 100644
--- a/DiscImageChef.Devices/ChangeLog
+++ b/DiscImageChef.Devices/ChangeLog
@@ -1,3 +1,9 @@
+2015-10-19  Natalia Portillo  <claunia@claunia.com>
+
+	* Device/Variables.cs:
+	  Make some variables readonly so they cannot be modified
+	  after construction.
+
 2015-10-19  Natalia Portillo  <claunia@claunia.com>
 
 	* Device/Variables.cs:
diff --git a/DiscImageChef.Devices/Device/Variables.cs b/DiscImageChef.Devices/Device/Variables.cs
index 5ceb19c35..53c80a840 100644
--- a/DiscImageChef.Devices/Device/Variables.cs
+++ b/DiscImageChef.Devices/Device/Variables.cs
@@ -46,12 +46,12 @@ namespace DiscImageChef.Devices
         object fd;
         bool error;
         int lastError;
-        DeviceType type;
-        string manufacturer;
-        string model;
-        string revision;
-        string serial;
-        Decoders.SCSI.PeripheralDeviceTypes scsiType;
+        readonly DeviceType type;
+        readonly string manufacturer;
+        readonly string model;
+        readonly string revision;
+        readonly string serial;
+        readonly Decoders.SCSI.PeripheralDeviceTypes scsiType;
 
         /// <summary>
         /// Gets the Platform ID for this device