diff --git a/tensordict/memmap_refact.py b/tensordict/memmap_refact.py
index c034c4365..445a32a1b 100644
--- a/tensordict/memmap_refact.py
+++ b/tensordict/memmap_refact.py
@@ -162,6 +162,30 @@ def from_handler(cls, handler, dtype, shape, index):
         out.parent_shape = shape
         return out
 
+    def __setstate__(self, state):
+        if 'filename' in state:
+            self.__dict__.update(type(self).from_filename(**state).__dict__)
+        else:
+            self.__dict__.update(type(self).from_handler(**state).__dict__)
+
+    def __getstate__(self):
+        if getattr(self, "_handler", None) is not None:
+            return {
+                'handler': self._handler,
+                'dtype': self.dtype,
+                'shape': self.parent_shape,
+                'index': self.index,
+            }
+        elif getattr(self, "_filename", None) is not None:
+            return {
+                'filename': self._filename,
+                'dtype': self.dtype,
+                'shape': self.parent_shape,
+                'index': self.index,
+            }
+        else:
+            raise RuntimeError("Could not find handler or filename.")
+
     def __reduce__(self):
         if getattr(self, "_handler", None) is not None:
             return type(self).from_handler, (