diff --git a/pus_tc/devs/imtq.py b/pus_tc/devs/imtq.py
index 7d376ab..46f532d 100644
--- a/pus_tc/devs/imtq.py
+++ b/pus_tc/devs/imtq.py
@@ -18,6 +18,12 @@ from tmtccmd.tc.pus_200_fsfw_modes import pack_mode_data, Modes
 from tmtccmd.util import ObjectIdU32
 
 
+class OpCodes:
+    ON = ["on"]
+    NORMAL = ["normal"]
+    OFF = ["off"]
+
+
 class ImtqSetIds:
     ENG_HK_SET = 1
     CAL_MTM_SET = 2
@@ -49,15 +55,15 @@ def pack_imtq_test_into(object_id: ObjectIdU32, q: DefaultPusQueueHelper, op_cod
         f"Testing ISIS IMTQ handler with object id: {object_id.as_hex_string}"
     )
 
-    if op_code == "0":
+    if op_code in OpCodes.OFF:
         q.add_log_cmd("IMTQ: Set mode off")
         command = pack_mode_data(object_id.as_bytes, Modes.OFF, 0)
         q.add_pus_tc(PusTelecommand(service=200, subservice=1, app_data=command))
-    if op_code == "1":
+    if op_code in OpCodes.ON:
         q.add_log_cmd("IMTQ: Set mode on")
         command = pack_mode_data(object_id.as_bytes, Modes.ON, 0)
         q.add_pus_tc(PusTelecommand(service=200, subservice=1, app_data=command))
-    if op_code == "2":
+    if op_code in OpCodes.NORMAL:
         q.add_log_cmd("IMTQ: Mode Normal")
         command = pack_mode_data(object_id.as_bytes, Modes.NORMAL, 0)
         q.add_pus_tc(PusTelecommand(service=200, subservice=1, app_data=command))