diff --git a/companion/src/storage/CMakeLists.txt b/companion/src/storage/CMakeLists.txt
index 2781b50b9..31dd86e9f 100644
--- a/companion/src/storage/CMakeLists.txt
+++ b/companion/src/storage/CMakeLists.txt
@@ -13,6 +13,7 @@ set(storage_NAMES
   categorized
   sdcard
   etx
+  otx
   yaml
 )
 
diff --git a/companion/src/storage/otx.cpp b/companion/src/storage/otx.cpp
new file mode 100644
index 000000000..90ea2bbf8
--- /dev/null
+++ b/companion/src/storage/otx.cpp
@@ -0,0 +1,116 @@
+/*
+ * Copyright (C) OpenTX
+ *
+ * Based on code named
+ *   th9x - http://code.google.com/p/th9x
+ *   er9x - http://code.google.com/p/er9x
+ *   gruvin9x - http://code.google.com/p/gruvin9x
+ *
+ * License GPLv2: http://www.gnu.org/licenses/gpl-2.0.html
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include "otx.h"
+#include "miniz.c"
+#include <QFile>
+
+#define MZ_ALLOCATION_SIZE    (32*1024)
+
+bool OtxFormat::load(RadioData & radioData)
+{
+  QFile file(filename);
+
+  if (!file.open(QFile::ReadOnly)) {
+    setError(tr("Error opening file %1:\n%2.").arg(filename).arg(file.errorString()));
+    return false;
+  }
+
+  QByteArray archiveContents = file.readAll();
+
+  qDebug() << "File" << filename << "read, size:" << archiveContents.size();
+
+  // open zip file
+  memset(&zip_archive, 0, sizeof(zip_archive));
+  if (!mz_zip_reader_init_mem(&zip_archive, archiveContents.data(), archiveContents.size(), 0)) {
+    qDebug() << tr("Error opening OTX archive %1").arg(filename);
+    return false;
+  }
+
+  bool result = CategorizedStorageFormat::load(radioData);
+  mz_zip_reader_end(&zip_archive);
+  return result;
+}
+
+bool OtxFormat::write(const RadioData & radioData)
+{
+  qDebug() << "Saving to archive" << filename;
+
+  memset(&zip_archive, 0, sizeof(zip_archive));
+  if (!mz_zip_writer_init_heap(&zip_archive, 0, MZ_ALLOCATION_SIZE)) {
+    setError(tr("Error initializing OTX archive writer"));
+    return false;
+  }
+
+  bool result = CategorizedStorageFormat::write(radioData);
+  if (result) {
+    // finalize archive and get contents
+    char * archiveContents;
+    size_t archiveSize;
+    if (mz_zip_writer_finalize_heap_archive(&zip_archive, (void **)&archiveContents, &archiveSize)) {
+      qDebug() << "Archive size" << archiveSize;
+      // write contents to file
+      QFile file(filename);
+      if (file.open(QIODevice::WriteOnly)) {
+        qint64 len = file.write(archiveContents, archiveSize);
+        if (len != (qint64)archiveSize) {
+          setError(tr("Error writing file %1:\n%2.").arg(filename).arg(file.errorString()));
+          result = false;
+        }
+      }
+      else {
+        setError(tr("Error creating OTX file %1:\n%2.").arg(filename).arg(file.errorString()));
+        result = false;
+      }
+    }
+    else {
+      setError(tr("Error creating OTX archive"));
+      result = false;
+    }
+  }
+
+  mz_zip_writer_end(&zip_archive);
+  return result;
+}
+
+bool OtxFormat::loadFile(QByteArray & filedata, const QString & filename)
+{
+  size_t size;
+  void * data = mz_zip_reader_extract_file_to_heap(&zip_archive, qPrintable(filename), &size, 0);
+  if (!data) {
+    return false;
+  }
+
+  qDebug() << QString("Extracted file %1, size=%2").arg(filename).arg(size);
+  filedata.clear();
+  filedata.append((char *)data, size);
+  mz_free(data);
+  return true;
+}
+
+bool OtxFormat::writeFile(const QByteArray & filedata, const QString & filename)
+{
+  if (!mz_zip_writer_add_mem(&zip_archive, filename.toStdString().c_str(), filedata.data(), filedata.size(), MZ_DEFAULT_LEVEL)) {
+    setError(tr("Error adding %1 to OTX archive").arg(filename));
+    return false;
+  }
+
+  return true;
+}
diff --git a/companion/src/storage/otx.h b/companion/src/storage/otx.h
new file mode 100644
index 000000000..da4923488
--- /dev/null
+++ b/companion/src/storage/otx.h
@@ -0,0 +1,53 @@
+/*
+ * Copyright (C) OpenTX
+ *
+ * Based on code named
+ *   th9x - http://code.google.com/p/th9x
+ *   er9x - http://code.google.com/p/er9x
+ *   gruvin9x - http://code.google.com/p/gruvin9x
+ *
+ * License GPLv2: http://www.gnu.org/licenses/gpl-2.0.html
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#ifndef _OTX_H_
+#define _OTX_H_
+
+#include "categorized.h"
+
+#include <QtCore>
+
+#define MINIZ_HEADER_FILE_ONLY
+#include "miniz.c"
+#undef MINIZ_HEADER_FILE_ONLY
+
+class OtxFormat : public CategorizedStorageFormat
+{
+  Q_DECLARE_TR_FUNCTIONS(OtxFormat)
+
+  public:
+    OtxFormat(const QString & filename):
+      CategorizedStorageFormat(filename)
+    {
+    }
+
+    virtual QString name() { return "otx"; }
+    virtual bool load(RadioData & radioData);
+    virtual bool write(const RadioData & radioData);
+
+  protected:
+    virtual bool loadFile(QByteArray & fileData, const QString & fileName);
+    virtual bool writeFile(const QByteArray & fileData, const QString & fileName);
+
+    mz_zip_archive zip_archive;
+};
+
+#endif // _OTX_H_
diff --git a/companion/src/storage/storage.cpp b/companion/src/storage/storage.cpp
index 8ec511769..ad7a7eabd 100644
--- a/companion/src/storage/storage.cpp
+++ b/companion/src/storage/storage.cpp
@@ -20,6 +20,7 @@
 
 #include "bineeprom.h"
 #include "eepe.h"
+#include "otx.h"
 #include "etx.h"
 #include "sdcard.h"
 #include "yaml.h"
@@ -65,6 +66,7 @@ void registerStorageFactories()
   registerStorageFactory(new DefaultStorageFactory<BinEepromFormat>("bin"));
   registerStorageFactory(new DefaultStorageFactory<EepeFormat>("eepe"));
   registerStorageFactory(new DefaultStorageFactory<HexEepromFormat>("hex"));
+  registerStorageFactory(new DefaultStorageFactory<OtxFormat>("otx"));
   registerStorageFactory(new DefaultStorageFactory<EtxFormat>("etx"));
   registerStorageFactory(new DefaultStorageFactory<YamlFormat>("yml"));
   registerStorageFactory(new SdcardStorageFactory());
@@ -86,17 +88,20 @@ bool Storage::load(RadioData & radioData)
 
   bool ret = false;
   foreach(StorageFactory * factory, registeredStorageFactories) {
-    StorageFormat * format = factory->instance(filename);
-    if (format->load(radioData)) {
-      board = format->getBoard();
-      setWarning(format->warning());
-      ret = true;
-      break;
+    if (factory->probe(filename)) {
+      StorageFormat * format = factory->instance(filename);
+      if (format->load(radioData)) {
+        board = format->getBoard();
+        setWarning(format->warning());
+        ret = true;
+        delete format;
+        break;
+      }
+      else {
+        setError(format->error());
+      }
+      delete format;
     }
-    else {
-      setError(format->error());
-    }
-    delete format;
   }
 
   return ret;