diff --git a/ArcFormats/CommonStreams.cs b/ArcFormats/CommonStreams.cs
index fa0547bf..531cf83e 100644
--- a/ArcFormats/CommonStreams.cs
+++ b/ArcFormats/CommonStreams.cs
@@ -438,6 +438,96 @@ namespace GameRes.Formats
         #endregion
     }
 
+    /// <summary>
+    /// Concatenation of the two input Streams.
+    /// </summary>
+    public class ConcatStream : InputProxyStream
+    {
+        Stream      m_second;
+        long        m_position;
+        Stream      m_active;
+
+        public ConcatStream (Stream first, Stream second) : base (first)
+        {
+            m_second = second;
+            m_position = 0;
+            m_active = first;
+        }
+
+        internal Stream  First { get { return BaseStream; } }
+        internal Stream Second { get { return m_second; } }
+
+        public override bool CanSeek  { get { return First.CanSeek && Second.CanSeek; } }
+        public override long Length   { get { return First.Length + Second.Length; } }
+        public override long Position
+        {
+            get { return m_position; }
+            set { m_position = value; }
+        }
+
+        public override int Read (byte[] buffer, int offset, int count)
+        {
+            if (First.CanSeek)
+            {
+                if (m_position >= First.Length)
+                {
+                    m_active = Second;
+                    m_active.Position = m_position - First.Length;
+                }
+                else
+                {
+                    m_active = First;
+                    m_active.Position = m_position;
+                }
+            }
+            int total_read = 0;
+            while (count > 0)
+            {
+                int read = m_active.Read (buffer, offset, count);
+                if (0 == read)
+                    break;
+                total_read += read;
+                m_position += read;
+                offset += read;
+                count -= read;
+            }
+            if (count > 0 && m_active != Second)
+            {
+                m_active = Second;
+                if (m_active.CanSeek)
+                    m_active.Position = 0;
+                int read = m_active.Read (buffer, offset, count);
+                m_position += read;
+                total_read += read;
+            }
+            return total_read;
+        }
+
+        public override long Seek (long offset, SeekOrigin origin)
+        {
+            if (SeekOrigin.Begin == origin)
+                Position = offset;
+            else if (SeekOrigin.Current == origin)
+                Position = m_position + offset;
+            else
+                Position = Length + offset;
+
+            return m_position;
+        }
+
+        bool _disposed = false;
+        protected override void Dispose (bool disposing)
+        {
+            if (!_disposed)
+            {
+                if (disposing)
+                    m_second.Dispose();
+                _disposed = true;
+                base.Dispose (disposing);
+            }
+        }
+    }
+
     public class XoredStream : ProxyStream
     {
         private byte        m_key;
diff --git a/ArcFormats/TamaSoft/ArcEPK.cs b/ArcFormats/TamaSoft/ArcEPK.cs
index e421f50e..25a02c1e 100644
--- a/ArcFormats/TamaSoft/ArcEPK.cs
+++ b/ArcFormats/TamaSoft/ArcEPK.cs
@@ -167,94 +167,4 @@ namespace GameRes.Formats.Tama
             return new ConcatStream (begin, end);
         }
     }
-
-    /// <summary>
-    /// Concatenation of the two input Streams.
-    /// </summary>
-    public class ConcatStream : InputProxyStream
-    {
-        Stream      m_second;
-        long        m_position;
-        Stream      m_active;
-
-        public ConcatStream (Stream first, Stream second) : base (first)
-        {
-            m_second = second;
-            m_position = 0;
-            m_active = first;
-        }
-
-        internal Stream  First { get { return BaseStream; } }
-        internal Stream Second { get { return m_second; } }
-
-        public override bool CanSeek  { get { return First.CanSeek && Second.CanSeek; } }
-        public override long Length   { get { return First.Length + Second.Length; } }
-        public override long Position
-        {
-            get { return m_position; }
-            set { m_position = value; }
-        }
-
-        public override int Read (byte[] buffer, int offset, int count)
-        {
-            if (First.CanSeek)
-            {
-                if (m_position >= First.Length)
-                {
-                    m_active = Second;
-                    m_active.Position = m_position - First.Length;
-                }
-                else
-                {
-                    m_active = First;
-                    m_active.Position = m_position;
-                }
-            }
-            int total_read = 0;
-            while (count > 0)
-            {
-                int read = m_active.Read (buffer, offset, count);
-                if (0 == read)
-                    break;
-                total_read += read;
-                m_position += read;
-                offset += read;
-                count -= read;
-            }
-            if (count > 0 && m_active != Second)
-            {
-                m_active = Second;
-                if (m_active.CanSeek)
-                    m_active.Position = 0;
-                int read = m_active.Read (buffer, offset, count);
-                m_position += read;
-                total_read += read;
-            }
-            return total_read;
-        }
-
-        public override long Seek (long offset, SeekOrigin origin)
-        {
-            if (SeekOrigin.Begin == origin)
-                Position = offset;
-            else if (SeekOrigin.Current == origin)
-                Position = m_position + offset;
-            else
-                Position = Length + offset;
-
-            return m_position;
-        }
-
-        bool _disposed = false;
-        protected override void Dispose (bool disposing)
-        {
-            if (!_disposed)
-            {
-                if (disposing)
-                    m_second.Dispose();
-                _disposed = true;
-                base.Dispose (disposing);
-            }
-        }
-    }
 }