diff --git a/include/em4x50.h b/include/em4x50.h
new file mode 100644
index 000000000..11b2509b7
--- /dev/null
+++ b/include/em4x50.h
@@ -0,0 +1,37 @@
+//-----------------------------------------------------------------------------
+// Copyright (C) 2020 tharexde
+//
+// This code is licensed to you under the terms of the GNU GPL, version 2 or,
+// at your option, any later version. See the LICENSE.txt file for the text of
+// the license.
+//-----------------------------------------------------------------------------
+// Low frequency EM4x50 structs
+//-----------------------------------------------------------------------------
+
+#ifndef EM4X50_H__
+#define EM4X50_H__
+
+typedef struct {
+    bool fwr_given;
+    bool lwr_given;
+    bool pwd_given;
+    bool newpwd_given;
+    uint8_t password[4];
+    uint8_t new_password[4];
+    uint8_t addresses[4];
+    uint8_t address;
+    uint8_t word[4];
+} em4x50_data_t;
+
+typedef struct {
+    uint8_t byte[4];
+    uint8_t row_parity[4];
+    uint8_t col_parity;
+    uint8_t stopbit;
+    bool rparity[4];
+    bool cparity[8];
+    bool stopparity;
+    bool parity;
+} em4x50_word_t;
+
+#endif /* EM4X50_H__ */