diff --git a/modpoll/arg_parser.py b/modpoll/arg_parser.py
index b22578d..bb10323 100644
--- a/modpoll/arg_parser.py
+++ b/modpoll/arg_parser.py
@@ -102,6 +102,7 @@ def get_parser():
     parser.add_argument(
         "--mqtt-qos",
         choices=[0, 1, 2],
+        type=int,
         default=0,
         help="MQTT QoS value. Defaults to 0",
     )