diff --git a/custom_components/xiaomi_gateway3/core/converters/mibeacon.py b/custom_components/xiaomi_gateway3/core/converters/mibeacon.py
index e0a2acee..ddc316f9 100644
--- a/custom_components/xiaomi_gateway3/core/converters/mibeacon.py
+++ b/custom_components/xiaomi_gateway3/core/converters/mibeacon.py
@@ -313,3 +313,19 @@ def decode(self, device: "XDevice", payload: dict, data: str):
         if value == device.extra.get("battery"):
             payload[self.attr] = value
         device.extra["battery"] = value
+
+
+class BLEScaleS400(BaseConv):
+    def decode(self, device: "XDevice", payload: dict, value: int):
+        weight = value & 0x7FF
+        heart_rate = (value >> 11) & 0xFF
+        impedance = value >> 18
+        if weight != 0:
+            payload["weight"] = weight / 10
+        if 0 < heart_rate < 127:
+            payload["heart_rate"] = heart_rate + 50
+        if impedance != 0:
+            if weight != 0:
+                payload["impedance_high"] = impedance / 10
+            else:
+                payload["impedance_low"] = impedance / 10
diff --git a/custom_components/xiaomi_gateway3/core/devices.py b/custom_components/xiaomi_gateway3/core/devices.py
index 8cb00bab..b805fad3 100644
--- a/custom_components/xiaomi_gateway3/core/devices.py
+++ b/custom_components/xiaomi_gateway3/core/devices.py
@@ -2016,6 +2016,16 @@
         MapConv("action", mi="5.e.1013.p.1", map={1: BUTTON_1_DOUBLE, 2: BUTTON_2_DOUBLE, 3: BUTTON_3_DOUBLE, 4: BUTTON_4_DOUBLE}),
         MapConv("action", mi="5.e.1014.p.1", map={1: BUTTON_1_HOLD, 2: BUTTON_2_HOLD, 3: BUTTON_3_HOLD, 4: BUTTON_4_HOLD}),
     ]
+}, {
+    # https://home.miot-spec.com/spec/yunmai.scales.ms107
+    18639: ["Xiaomi", "Body Composition Scale S400", "BHR7793GL", "yunmai.scales.ms103"],
+    "spec": [
+        BaseConv("weight", "sensor", entity={"icon": "mdi:human", "units": "kg"}),
+        BaseConv("heart_rate", "sensor", entity={"icon": "mdi:heart-pulse", "units": "bpm"}),
+        BaseConv("impedance_low", "sensor", entity={"icon": "mdi:omega", "units": "ohm"}),
+        BaseConv("impedance_high", "sensor", entity={"icon": "mdi:omega", "units": "ohm"}),
+        BLEScaleS400("raw_data", mi="11.e.1022.p.2"),
+    ],
 }, {
     # https://home.miot-spec.com/spec/izq.sensor_occupy.ble
     18788: ["ZiQing", "IZQ Presence Sensor Loong", "IZQ-BLE", "izq.sensor_occupy.ble"],
diff --git a/tests/test_conv_ble.py b/tests/test_conv_ble.py
index a379178e..21b5185c 100644
--- a/tests/test_conv_ble.py
+++ b/tests/test_conv_ble.py
@@ -328,3 +328,32 @@ def test_14523():
 
     p = device.decode({"eid": 18956, "edata": ""})
     assert p == {"action": "single"}
+
+
+def test_18639():
+    device = XDevice(18639)
+
+    p = device.decode(
+        {"siid": 11, "eiid": 1022, "arguments": [{"piid": 2, "value": 260823}]}
+    )
+    assert p == {"weight": 72.7}
+
+    p = device.decode(
+        {"siid": 11, "eiid": 1022, "arguments": [{"piid": 2, "value": 1338768096}]}
+    )
+    assert p == {"impedance_high": 510.6, "weight": 73.6}
+
+    p = device.decode(
+        {"siid": 11, "eiid": 1022, "arguments": [{"piid": 2, "value": 1234960384}]}
+    )
+    assert p == {"impedance_low": 471.1}
+
+    p = device.decode(
+        {"siid": 11, "eiid": 1022, "arguments": [{"piid": 2, "value": 1343068894}]}
+    )
+    assert p == {"impedance_high": 512.3, "weight": 73.4}
+
+    p = device.decode(
+        {"siid": 11, "eiid": 1022, "arguments": [{"piid": 2, "value": 1240727552}]}
+    )
+    assert p == {"impedance_low": 473.3}