diff --git a/custom_components/tekmar_482/const.py b/custom_components/tekmar_482/const.py
index 11374e1..89fa685 100644
--- a/custom_components/tekmar_482/const.py
+++ b/custom_components/tekmar_482/const.py
@@ -167,6 +167,7 @@ class ThaActiveDemand(IntEnum):
     105801: ThaType.SNOWMELT,
     108401: ThaType.SNOWMELT,
     108402: ThaType.SNOWMELT,
+    10599181: ThaType.THERMOSTAT,  # alternate for 99301
 }
 
 DEVICE_FEATURES = {
@@ -270,6 +271,16 @@ class ThaActiveDemand(IntEnum):
         "snow": 0,
         "emer": 0,
     },
+    10599181: {  # alternate for 99301
+        "model": "541",
+        "type": DEVICE_TYPES[10599181],
+        "heat": 1,
+        "cool": 0,
+        "fan": 0,
+        "humid": 0,
+        "snow": 0,
+        "emer": 0,
+    },
     99302: {
         "model": "542",
         "type": DEVICE_TYPES[99302],