diff --git a/src/tdastro/base_models.py b/src/tdastro/base_models.py
index fc038f1d..c2c9e1bf 100644
--- a/src/tdastro/base_models.py
+++ b/src/tdastro/base_models.py
@@ -335,6 +335,28 @@ def get_dependencies(self, nodes=None):
         return nodes
 
 
+class SingleVariableNode(ParameterizedNode):
+    """A ParameterizedNode holding a single pre-defined variable.
+
+    Notes
+    -----
+    Often used for testing, but can be used to make graph dependencies clearer.
+
+    Parameters
+    ----------
+    name : `str`
+        The parameter name.
+    value : any
+        The parameter value.
+    **kwargs : `dict`, optional
+        Any additional keyword arguments.
+    """
+
+    def __init__(self, name, value, **kwargs):
+        super().__init__(**kwargs)
+        self.add_parameter(name, value, required=True, **kwargs)
+
+
 class FunctionNode(ParameterizedNode):
     """A class to wrap functions and their argument settings.
 
diff --git a/tests/tdastro/test_base_models.py b/tests/tdastro/test_base_models.py
index c2e25abb..46ed5e74 100644
--- a/tests/tdastro/test_base_models.py
+++ b/tests/tdastro/test_base_models.py
@@ -2,7 +2,7 @@
 
 import numpy as np
 import pytest
-from tdastro.base_models import FunctionNode, ParameterizedNode
+from tdastro.base_models import FunctionNode, ParameterizedNode, SingleVariableNode
 
 
 def _sampler_fun(**kwargs):
@@ -29,20 +29,6 @@ def _test_func(value1, value2):
     return value1 + value2
 
 
-class SingleModel(ParameterizedNode):
-    """A test class for the ParameterizedNode.
-
-    Attributes
-    ----------
-    value1 : `float`
-        The first value.
-    """
-
-    def __init__(self, value1, **kwargs):
-        super().__init__(**kwargs)
-        self.add_parameter("value1", value1, required=True, **kwargs)
-
-
 class PairModel(ParameterizedNode):
     """A test class for the ParameterizedNode.
 
@@ -249,7 +235,7 @@ def test_parameterized_node_seed():
     model_a = PairModel(value1=0.5, value2=0.5, graph_base_seed=10, node_identifier="A")
     model_b = PairModel(value1=0.5, value2=0.5, graph_base_seed=10, node_identifier="B")
     model_c = PairModel(value1=0.5, value2=0.5, graph_base_seed=10, node_identifier="A")
-    model_d = SingleModel(value1=0.5, node_identifier="A")
+    model_d = SingleVariableNode("value1", 0.5, node_identifier="A")
     assert model_a._object_seed != model_b._object_seed
     assert model_a._object_seed == model_c._object_seed
     assert model_a._object_seed != model_d._object_seed
@@ -267,6 +253,12 @@ def test_parameterized_node_seed():
     assert model_d._object_seed != model_c._object_seed
 
 
+def test_single_variable_node():
+    """Test that we can create and query a SingleVariableNode."""
+    node = SingleVariableNode("A", 10.0)
+    assert node.A == 10
+
+
 def test_function_node_basic():
     """Test that we can create and query a FunctionNode."""
     my_func = FunctionNode(_test_func, value1=1.0, value2=2.0)