diff --git a/qualang_tools/octave_tools/octave_tools.py b/qualang_tools/octave_tools/octave_tools.py
index b1ad6604..c2304c77 100644
--- a/qualang_tools/octave_tools/octave_tools.py
+++ b/qualang_tools/octave_tools/octave_tools.py
@@ -208,10 +208,10 @@ def octave_calibration_tool(
     :param lo_frequencies: single value or list of LO frequencies to calibrate in Hz.
     :param intermediate_frequencies: single value or list of Intermediate frequencies to calibrate in Hz.
     """
-    if not isinstance(lo_frequencies, Union[list, np.ndarray]):
+    if not isinstance(lo_frequencies, (list, np.ndarray)):
         lo_frequencies = [lo_frequencies]
 
-    if not isinstance(intermediate_frequencies, Union[list, np.ndarray]):
+    if not isinstance(intermediate_frequencies, (list, np.ndarray)):
         intermediate_frequencies = [intermediate_frequencies]
 
     for lo in lo_frequencies:
diff --git a/qualang_tools/wirer/connectivity/connectivity_transmon_interface.py b/qualang_tools/wirer/connectivity/connectivity_transmon_interface.py
index 19156fb8..6541de46 100644
--- a/qualang_tools/wirer/connectivity/connectivity_transmon_interface.py
+++ b/qualang_tools/wirer/connectivity/connectivity_transmon_interface.py
@@ -28,6 +28,12 @@ def add_qubit_drive_lines(self, qubits: QubitsType, triggered: bool = False, con
                                     triggered, constraints, elements)
 
 
+    def add_qubit_charge_lines(self, qubits: QubitsType, constraints: ChannelSpec = None):
+        elements = self._make_qubit_elements(qubits)
+        return self.add_wiring_spec(WiringFrequency.DC, WiringIOType.OUTPUT, WiringLineType.CHARGE,
+                                    False, constraints, elements)
+
+
     def add_qubit_flux_lines(self, qubits: QubitsType, constraints: ChannelSpec = None):
         elements = self._make_qubit_elements(qubits)
         return self.add_wiring_spec(WiringFrequency.DC, WiringIOType.OUTPUT, WiringLineType.FLUX,
diff --git a/qualang_tools/wirer/connectivity/wiring_spec.py b/qualang_tools/wirer/connectivity/wiring_spec.py
index 29bafa83..d5ef351e 100644
--- a/qualang_tools/wirer/connectivity/wiring_spec.py
+++ b/qualang_tools/wirer/connectivity/wiring_spec.py
@@ -15,6 +15,7 @@ class WiringLineType(Enum):
     RESONATOR = "rr"
     DRIVE = "xy"
     FLUX = "z"
+    CHARGE = "q"
     COUPLER = "c"
 
 class WiringSpec:
diff --git a/qualang_tools/wirer/visualizer/visualizer.py b/qualang_tools/wirer/visualizer/visualizer.py
index 3c3156e3..b712c86c 100644
--- a/qualang_tools/wirer/visualizer/visualizer.py
+++ b/qualang_tools/wirer/visualizer/visualizer.py
@@ -43,6 +43,7 @@ def prepare_available_channel_annotations(available_channels: InstrumentChannels
 def get_color_for_line_type(line_type) -> str:
     color_map = {
         WiringLineType.FLUX: "powderblue",
+        WiringLineType.CHARGE: "lavender",
         WiringLineType.RESONATOR: "peachpuff",
         WiringLineType.DRIVE: "lemonchiffon",
         WiringLineType.COUPLER: "thistle"
diff --git a/qualang_tools/wirer/wirer/wirer.py b/qualang_tools/wirer/wirer/wirer.py
index 18f09b0e..23175745 100644
--- a/qualang_tools/wirer/wirer/wirer.py
+++ b/qualang_tools/wirer/wirer/wirer.py
@@ -22,6 +22,7 @@ def allocate_wiring(connectivity: Connectivity, instruments: Instruments,
         WiringLineType.RESONATOR,
         WiringLineType.DRIVE,
         WiringLineType.FLUX,
+        WiringLineType.CHARGE,
         WiringLineType.COUPLER,
     ]
 
diff --git a/tests/wirer/test_wirer_lf_charge.py b/tests/wirer/test_wirer_lf_charge.py
new file mode 100644
index 00000000..a2694bf1
--- /dev/null
+++ b/tests/wirer/test_wirer_lf_charge.py
@@ -0,0 +1,22 @@
+import pytest
+
+from qualang_tools.wirer import *
+
+visualize_flag = pytest.visualize_flag
+
+def test_5q_allocation_flux_charge(instruments_2lf_2mw):
+    qubits = [1, 2, 3, 4, 5]
+    qubit_pairs = [(1, 2), (2, 3), (3, 4), (4, 5)]
+
+    connectivity = Connectivity()
+    connectivity.add_resonator_line(qubits=qubits, constraints=mw_fem_spec(slot=7))
+    connectivity.add_qubit_flux_lines(qubits=qubits)
+    connectivity.add_qubit_charge_lines(qubits=qubits)
+    connectivity.add_qubit_pair_flux_lines(qubit_pairs=qubit_pairs, constraints=lf_fem_spec(out_slot=2))
+
+    allocate_wiring(connectivity, instruments_2lf_2mw)
+
+    print(connectivity.elements)
+
+    if visualize_flag:
+        visualize(connectivity.elements, instruments_2lf_2mw.available_channels)