diff --git a/src/storage/model.cpp b/src/storage/model.cpp
index b3f824d..9be8f96 100644
--- a/src/storage/model.cpp
+++ b/src/storage/model.cpp
@@ -212,7 +212,7 @@ void define_sparse_model(py::module& m) {
     ;
     py::class_<SparsePomdp<double>, std::shared_ptr<SparsePomdp<double>>>(m, "SparsePomdp", "POMDP in sparse representation", mdp)
         .def(py::init<SparsePomdp<double>>(), py::arg("other_model"))
-        .def(py::init<ModelComponents<double> const&, bool>(), py::arg("components"), py::arg("canonicFlag")=false) //todo tests
+        .def(py::init<ModelComponents<double> const&, bool>(), py::arg("components"), py::arg("canonic_flag")=false) //todo tests
         .def("__str__", &getModelInfoPrinter)
         .def("get_observation", &SparsePomdp<double>::getObservation, py::arg("state"))
         .def_property_readonly("observations", &SparsePomdp<double>::getObservations)
@@ -234,7 +234,6 @@ void define_sparse_model(py::module& m) {
     ;
 
     py::class_<SparseRewardModel<double>>(m, "SparseRewardModel", "Reward structure for sparse models")
-        //todo init?
         .def_property_readonly("has_state_rewards", &SparseRewardModel<double>::hasStateRewards)
         .def_property_readonly("has_state_action_rewards", &SparseRewardModel<double>::hasStateActionRewards)
         .def_property_readonly("has_transition_rewards", &SparseRewardModel<double>::hasTransitionRewards)
diff --git a/src/storage/modelcomponents.cpp b/src/storage/modelcomponents.cpp
index 95a738c..2adbcb6 100644
--- a/src/storage/modelcomponents.cpp
+++ b/src/storage/modelcomponents.cpp
@@ -25,15 +25,16 @@ template<typename ValueType> using SparseModelComponents = storm::storage::spars
 
 void define_sparse_modelcomponents(py::module& m) {
 
-    py::class_<SparseModelComponents<double>>(m, "SparseModelComponents", "ModelComponents description..") //todo
+    // shared_ptr? todo
+    py::class_<SparseModelComponents<double>, std::shared_ptr<SparseModelComponents<double>>>(m, "SparseModelComponents", "ModelComponents description..") //todo
 
         .def(py::init<SparseMatrix<double> const&, StateLabeling const&, std::unordered_map<std::string, SparseRewardModel<double>> const&,
             bool, boost::optional<BitVector> const&, boost::optional<SparseMatrix<storm::storage::sparse::state_type>> const&>(),
-            py::arg("transition_matrix"), py::arg("state_labeling") = storm::models::sparse::StateLabeling(),
+            py::arg("transition_matrix") = SparseMatrix<double>(), py::arg("state_labeling") = storm::models::sparse::StateLabeling(),
             py::arg("reward_models") =  std::unordered_map<std::string, SparseRewardModel<double>>(), py::arg("rate_transitions") = false,
             py::arg("markovian_states") = boost::none, py::arg("player1_matrix") = boost::none)
 
-        //.def(py::init<>()) // for rvalue ? todo
+
 
         // General components (for all model types)
         .def_readwrite("transition_matrix", &SparseModelComponents<double>::transitionMatrix)
diff --git a/tests/storage/test_modelcomponents.py b/tests/storage/test_modelcomponents.py
new file mode 100644
index 0000000..2334016
--- /dev/null
+++ b/tests/storage/test_modelcomponents.py
@@ -0,0 +1,65 @@
+import stormpy
+import stormpy.logic
+from helpers.helper import get_example_path
+import pytest
+
+
+class TestSparseModel:
+    def test_init_default(self):
+        components = stormpy.SparseModelComponents()
+
+        assert components.state_labeling.get_labels() == set()
+        assert components.reward_models == {}
+        assert components.transition_matrix.nr_rows == 0
+        assert components.transition_matrix.nr_columns == 0
+        assert components.markovian_states is None
+        assert components.player1_matrix is None
+        assert not components.rate_transitions
+
+    # def test_init(self):
+    # todo Build simple transition matrix etc
+    # transition_matrix =
+
+
+    def test_dtmc_modelcomponents(self):
+        program = stormpy.parse_prism_program(get_example_path("dtmc", "die.pm"))
+        model = stormpy.build_model(program)
+
+        components = stormpy.SparseModelComponents(transition_matrix=model.transition_matrix,
+                                                   state_labeling=model.labeling,
+                                                   reward_models=model.reward_models)
+
+        dtmc = stormpy.storage.SparseDtmc(components)
+
+        assert dtmc.model_type == stormpy.ModelType.DTMC
+        assert dtmc.initial_states == [0]
+        assert dtmc.nr_states == 13
+        for state in dtmc.states:
+            assert len(state.actions) <= 1
+        assert dtmc.labeling.get_labels() == {'init', 'deadlock', 'done', 'one', 'two', 'three', 'four', 'five', 'six'}
+        assert dtmc.nr_transitions == 20
+        assert len(dtmc.reward_models) == 1
+        assert not dtmc.reward_models["coin_flips"].has_state_rewards
+        assert dtmc.reward_models["coin_flips"].has_state_action_rewards
+        for reward in dtmc.reward_models["coin_flips"].state_action_rewards:
+            assert reward == 1.0 or reward == 0.0
+        assert not dtmc.reward_models["coin_flips"].has_transition_rewards
+        assert not dtmc.supports_parameters
+
+
+    def test_pmdp_modelcomponents(self):
+        program = stormpy.parse_prism_program(get_example_path("pmdp", "two_dice.nm"))
+        model = stormpy.build_parametric_model(program)
+
+ 
+    def test_ma_modelcomponents(self):
+        program = stormpy.parse_prism_program(get_example_path("ma", "simple.ma"), False, True)
+        formulas = stormpy.parse_properties_for_prism_program("Pmax=? [ F<=2 s=2 ]", program)
+        model = stormpy.build_model(program, formulas)
+        #todo create mc
+
+        assert model.nr_states == 4
+        assert model.nr_transitions == 7
+        assert model.model_type == stormpy.ModelType.MA
+        assert not model.supports_parameters
+        assert type(model) is stormpy.SparseMA