diff --git a/efi-board-id.cs b/efi-board-id.cs
index d9bab7c..c9853de 100644
--- a/efi-board-id.cs
+++ b/efi-board-id.cs
@@ -1,41 +1,58 @@
-// David R, 22.02.2023
-// C# code to pull a Mac board-id from compatible EFIROM dumps.
+// ROMHelper.cs - David R - 22.02.2023
+// CSharp.NET code to pull a Mac board-id from compatible EFIROM dumps.
 
 using System;
 using System.IO;
+using System.Text;
 
 namespace MacTools.EFI
 {
     class ROMHelper
     {
-        const int BID_OFFSET = 0x1060;   // Offset in PDR region, actual board-id is at 0x1064h (BID_OFFSET + BID_POS).
-        const int BID_DATA_LEN = 0x12;   // Length of the data we want.
-        const int BID_POS = 0x4;         // Position of board-id.
-        const int BID_LEN = 0x8;         // Length of board-id (8 bytes).
+        const int BID_DATA_OFFSET = 0x1060;   // Offset in PDR region, actual board-id is at 0x1064h (BID_OFFSET + BID_POS).
+        const int BID_DATA_LEN = 0x12;        // Lenth of the data we want.
+        const int BID_POS = 0x4;              // Position of board-id.
+        const int BID_LEN = 0x8;              // Length of board-id (8 bytes).
 
-        public static string getBoardIdFromEfiROM(string filePath)
+        private static readonly byte[] hexDescriptor = { 0x5A, 0xA5, 0xF0, 0x0F };    // Descriptor signature
+        private static readonly byte[] hexBoardId = { 0x7C, 0x00, 0x00, 0x19 };       // board-id signature
+
+        public static string strGetBoardIdFromEfiROM(string filePath)
         {
             try
             {
                 using (FileStream fileStream = new FileStream(filePath, FileMode.Open))
                 {
-                    using (BinaryReader binaryReader = new BinaryReader(fileStream))
+                    using (BinaryReader binaryReader = new BinaryReader(fileStream, Encoding.Unicode))
                     {
-                        string strBcBytes = string.Empty;
-                        byte[] bIdBytes = new byte[BID_DATA_LEN];
-                        binaryReader.BaseStream.Position = BID_OFFSET; // Seek to marker offset.
-                        bIdBytes = binaryReader.ReadBytes(BID_DATA_LEN); // Read 12 bytes (Marker + Board ID in hex).
+                        byte[] bytesDescriptor = new byte[0x4];
+                        byte[] bytesBoardId = new byte[BID_DATA_LEN];
+
+                        binaryReader.BaseStream.Position = 0x10;
+                        bytesDescriptor = binaryReader.ReadBytes(0x4);
 
-                        // Looking for 7C000019h in the first 4 bytes skipping 0x00
-                        if (bIdBytes[0] == 0x7C && bIdBytes[3] == 0x19)
+                        // Compare magic bytes to expected bytes
+                        if (bytesDescriptor[0] == hexDescriptor[0] && bytesDescriptor[1] == hexDescriptor[1] &&
+                            bytesDescriptor[2] == hexDescriptor[2] && bytesDescriptor[3] == hexDescriptor[3])
                         {
-                            // Found bytes, return the board-id.
-                            strBcBytes = BitConverter.ToString(bIdBytes, BID_POS, BID_LEN).Replace("-", ""); // Spit out board-id hexadecimal
-                            return string.Concat("Mac-", strBcBytes); // Return final string
+                            binaryReader.BaseStream.Position = BID_DATA_OFFSET;
+                            bytesBoardId = binaryReader.ReadBytes(BID_DATA_LEN);
+
+                            // Looking for 7C000019h in the first 4 bytes skipping 0x00.
+                            if (bytesBoardId[0] == hexBoardId[0] && bytesBoardId[3] == hexBoardId[3])
+                            {
+                                // Found bytes, return the board-id.
+                                string strBcBytes = BitConverter.ToString(bytesBoardId, BID_POS, BID_LEN).Replace("-", ""); // Spit out board-id hexadecimal.
+                                return string.Concat("Mac-", strBcBytes); // Return final string
+                            }
+                            else
+                            {
+                                return "Expected bytes not found at 0x1060h."; // Expected bytes not found.
+                            }
                         }
                         else
                         {
-                            return "Marker not found at 0x1060h.";
+                            return "No descriptor, not a valid binary?"; // Descriptor not found.
                         }
                     }
                 }
@@ -46,4 +63,4 @@ public static string getBoardIdFromEfiROM(string filePath)
             }
         }
     }
-}
+}
\ No newline at end of file