diff --git a/pygem/params.py b/pygem/params.py
index 2aee191..73fe642 100644
--- a/pygem/params.py
+++ b/pygem/params.py
@@ -353,9 +353,7 @@ def _set_box_dimensions(self, min_xyz, max_xyz):
 			the bounding box in XYZ respectively
 		"""
 		dims = [max_xyz[i] - min_xyz[i] for i in range(3)]
-		self.lenght_box_x = dims[0]
-		self.lenght_box_y = dims[1]
-		self.lenght_box_z = dims[2]
+		self.lenght_box = np.asarray(dims)
 
 	def _set_position_of_vertices(self):
 		"""
@@ -364,21 +362,18 @@ def _set_position_of_vertices(self):
 		parallelepiped -- the second half of the box is created as a mirror
 		reflection of the first four vertices.
 		"""
-		origin_array = np.array(self.origin_box)
-		dim = [self.lenght_box_x, self.lenght_box_y, self.lenght_box_z]
-		self.position_vertex_0 = origin_array
-		self.position_vertex_1 = origin_array + np.array([dim[0], .0, .0])
-		self.position_vertex_2 = origin_array + np.array([.0, dim[1], .0])
-		self.position_vertex_3 = origin_array + np.array([.0, .0, dim[2]])
+		self.position_vertex_0 = self.origin_box
+		self.position_vertex_1 = self.origin_box + np.array([self.lenght_box[0], .0, .0])
+		self.position_vertex_2 = self.origin_box + np.array([.0, self.lenght_box[1], .0])
+		self.position_vertex_3 = self.origin_box + np.array([.0, .0, self.lenght_box[2]])
 
 	def _set_mapping(self):
 		"""
 		This method sets mapping from physcial domain to the reference domain
 		(``psi_mapping``) as well as inverse mapping (``inv_psi_mapping``).
 		"""
-		dim = [self.lenght_box_x, self.lenght_box_y, self.lenght_box_z]
-		self.psi_mapping = np.diag([1. / dim[i] for i in range(3)])
-		self.inv_psi_mapping = np.diag(dim)
+		self.psi_mapping = np.diag([1. / self.lenght_box[i] for i in range(3)])
+		self.inv_psi_mapping = np.diag(self.lenght_box)
 
 	def _set_transformation_params_to_zero(self):
 		"""
diff --git a/tests/test_ffdparams.py b/tests/test_ffdparams.py
index 57adc1d..a7ab0bb 100644
--- a/tests/test_ffdparams.py
+++ b/tests/test_ffdparams.py
@@ -294,20 +294,26 @@ def test_write_parameters(self):
 		self.assertTrue(filecmp.cmp(outfilename, outfilename_expected))
 		os.remove(outfilename)
 
-	def test_print_info(self):
+	def test_print(self):
 		params = ffdp.FFDParameters(n_control_points=[3, 2, 2])
 		print(params)
 
-	def test_build_bounding_box(self):
+	def test_build_bounding_box_1(self):
+		origin = np.array([0., 0., 0.])
+		tops = np.array([1., 1., 1.])
+		cube = BRepPrimAPI_MakeBox(*tops).Shape()
+		params = ffdp.FFDParameters()
+		params.build_bounding_box(cube)
+
+		np.testing.assert_array_almost_equal(params.lenght_box, tops, decimal=5)
+
+	def test_build_bounding_box_2(self):
 		origin = np.array([0., 0., 0.])
 		tops = np.array([1., 1., 1.])
 		cube = BRepPrimAPI_MakeBox(*tops).Shape()
 		params = ffdp.FFDParameters()
 		params.build_bounding_box(cube)
 
-		self.assertAlmostEqual(params.lenght_box_x, tops[0], places=5)
-		self.assertAlmostEqual(params.lenght_box_y, tops[1], places=5)
-		self.assertAlmostEqual(params.lenght_box_z, tops[2], places=5)
 		np.testing.assert_almost_equal(params.position_vertex_0, origin, decimal=5)
 		np.testing.assert_almost_equal(params.position_vertex_1, [1., 0., 0.], decimal=5)
 		np.testing.assert_almost_equal(params.position_vertex_2, [0., 1., 0.], decimal=5)
@@ -319,9 +325,7 @@ def test_set_box_dimension(self):
 		params = ffdp.FFDParameters()
 		params.origin_box = origin
 		params._set_box_dimensions(origin, tops)
-		self.assertEqual(params.lenght_box_x, tops[0])
-		self.assertEqual(params.lenght_box_y, tops[1])
-		self.assertEqual(params.lenght_box_z, tops[2])
+		np.testing.assert_array_almost_equal(params.lenght_box, tops)
 
 	def test_set_position_of_vertices(self):
 		vertex_0 = [0., 0., 0.]