diff --git a/aiowialon/api.py b/aiowialon/api.py
index bf8afe8..be0457c 100644
--- a/aiowialon/api.py
+++ b/aiowialon/api.py
@@ -92,7 +92,18 @@ def timeout(self, timeout: float) -> None:
 
     @property
     def session_lock(self) -> Callable:
-        """Decorator to set exclusive session access for long critical operations"""
+        """
+        Decorator to set exclusive session access for long critical operations
+
+        >>> # Example
+        >>> from aiowialon import Wialon
+        >>> wialon = Wialon()
+        >>>
+        >>> @wialon.avl_event_handler()
+        >>> @wialon.session_lock  # exclusive session lock for callback's frame
+        >>> async def unit_event(event: AvlEvent):
+        >>>     await wialon.core_search_item(id=event.data.i, flags=1)
+        """
 
         return self.__exclusive_session_lock.lock
 
diff --git a/examples/aiolock.py b/examples/aiolock.py
index e0f6396..91ba5bb 100644
--- a/examples/aiolock.py
+++ b/examples/aiolock.py
@@ -39,7 +39,7 @@ async def register_avl_events(session_login):
 @wialon.avl_event_handler()
 @wialon.session_lock  # exclusive session lock for callback's frame
 async def unit_event(event: AvlEvent):
-    await wialon.core_search_item(id=734455, flags=1)
+    await wialon.core_search_item(id=event.data.i, flags=1)
     print("Handler got event:", event)
     for i in range(5):
         print("Waiting exclusive operation", i, "item:", event.data.i)