diff --git a/FIAT/dual_set.py b/FIAT/dual_set.py
index 26759ba7..dd26381d 100644
--- a/FIAT/dual_set.py
+++ b/FIAT/dual_set.py
@@ -8,11 +8,11 @@
 
 
 class DualSet(object):
-    def __init__(self, nodes, ref_el, entity_ids):
+    def __init__(self, nodes, ref_el, entity_ids, entity_block_sizes=[1, 1, 1, 1]):
         self.nodes = nodes
         self.ref_el = ref_el
         self.entity_ids = entity_ids
-
+        self.entity_block_sizes = entity_block_sizes
         # Compute the nodes on the closure of each sub_entity.
         self.entity_closure_ids = {}
         for dim, entities in ref_el.sub_entities.items():
@@ -54,6 +54,9 @@ def to_riesz(self, poly_set):
 
         return self.mat
 
+    def get_entity_block_sizes(self):
+        return self.entity_block_sizes
+
 
 def make_entity_closure_ids(ref_el, entity_ids):
     entity_closure_ids = {}
diff --git a/FIAT/nedelec.py b/FIAT/nedelec.py
index bb7bdb21..af08b15f 100644
--- a/FIAT/nedelec.py
+++ b/FIAT/nedelec.py
@@ -198,7 +198,7 @@ def __init__(self, ref_el, degree):
             num_internal_dof = sd * Pkm1_at_qpts.shape[0]
             entity_ids[2][0] = list(range(cur, cur + num_internal_dof))
 
-        super(NedelecDual2D, self).__init__(nodes, ref_el, entity_ids)
+        super(NedelecDual2D, self).__init__(nodes, ref_el, entity_ids, [1, 1, 2, -1])
 
 
 class NedelecDual3D(dual_set.DualSet):
@@ -273,7 +273,7 @@ def __init__(self, ref_el, degree):
             num_internal_dof = Pkm2_at_qpts.shape[0] * sd
             entity_ids[3][0] = list(range(cur, cur + num_internal_dof))
 
-        super(NedelecDual3D, self).__init__(nodes, ref_el, entity_ids)
+        super(NedelecDual3D, self).__init__(nodes, ref_el, entity_ids, [1, 1, 2, 3])
 
 
 class Nedelec(finite_element.CiarletElement):
diff --git a/FIAT/raviart_thomas.py b/FIAT/raviart_thomas.py
index 01ce4dc2..218550d8 100644
--- a/FIAT/raviart_thomas.py
+++ b/FIAT/raviart_thomas.py
@@ -124,7 +124,12 @@ def __init__(self, ref_el, degree):
                                                                  degree - 1)
             entity_ids[sd][0] = list(range(cur, cur + num_internal_nodes * sd))
 
-        super(RTDualSet, self).__init__(nodes, ref_el, entity_ids)
+        if sd == 2:
+            entity_block_sizes = [1, 1, 2, -1]
+        else:
+            entity_block_sizes = [1, 1, 1, 3]
+
+        super(RTDualSet, self).__init__(nodes, ref_el, entity_ids, entity_block_sizes)
 
 
 class RaviartThomas(finite_element.CiarletElement):