diff --git a/lib/mp4.cpp b/lib/mp4.cpp
index d72aa0d0..44069fca 100644
--- a/lib/mp4.cpp
+++ b/lib/mp4.cpp
@@ -531,4 +531,12 @@ namespace MP4{
     }
     return r;
   }
+  
+  MFHD::MFHD() : Box("mfhd") {
+    setInt32(0,0);
+  }
+  
+  void MFHD::setSequenceNumber( long newSequenceNumber ) {
+    setInt32( newSequenceNumber, 4 );
+  }
 };
diff --git a/lib/mp4.h b/lib/mp4.h
index 6089b516..7c1692a9 100644
--- a/lib/mp4.h
+++ b/lib/mp4.h
@@ -119,5 +119,10 @@ namespace MP4{
       std::deque<std::string> qualityModifiers;
       std::deque<segmentRun> segmentRunTable;
   };//ASRT Box
-
+  
+  class MFHD : public Box {
+    public:
+      MFHD();
+      void setSequenceNumber( long newSequenceNumber );
+  };//MFHD Box
 };