diff --git a/src/anemoi/transform/filters/rodeo-opera-mask.py b/src/anemoi/transform/filters/rodeo-opera-mask.py
new file mode 100644
index 0000000..91205d9
--- /dev/null
+++ b/src/anemoi/transform/filters/rodeo-opera-mask.py
@@ -0,0 +1,61 @@
+# (C) Copyright 2024 Anemoi contributors.
+#
+# This software is licensed under the terms of the Apache Licence Version 2.0
+# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
+#
+# In applying this licence, ECMWF does not waive the privileges and immunities
+# granted to it by virtue of its status as an intergovernmental organisation
+# nor does it submit to any jurisdiction.
+
+import numpy as np
+
+from . import filter_registry
+from .base import SimpleFilter
+
+
+def mask_opera(tp, quality, mask):
+    print("✅✅", quality)
+    print("✅✅✅", tp)
+    tp[quality == 75] = np.nan
+    tp[mask >= 5] = np.nan
+    return tp
+
+
+@filter_registry.register("rodeo_opera_mask")
+class RodeoOperaMask(SimpleFilter):
+    """A filter to select only good quality data i nrodeo opera data."""
+
+    def __init__(
+        self,
+        *,
+        tp="tp",
+        quality="quality",
+        mask="mask",
+        output="tp_masked",
+    ):
+        self.tp = tp
+        self.quality = quality
+        self.tp_masked = output
+        self.mask = mask
+
+    def forward(self, data):
+        return self._transform(
+            data,
+            self.forward_transform,
+            self.tp,
+            self.quality,
+            self.mask,
+        )
+
+    def backward(self, data):
+        raise NotImplementedError("RodeoOperaMask is not reversible")
+
+    def forward_transform(self, tp, quality, mask):
+        """Mask out rodeo Opear data"""
+
+        tp_masked = mask_opera(tp=tp.to_numpy(), quality=quality.to_numpy(), mask=mask.to_numpy())
+
+        yield self.new_field_from_numpy(tp_masked, template=tp, param=self.tp_masked)
+
+    def backward_transform(self, tp):
+        raise NotImplementedError("RodeoOperaMask is not reversible")