diff --git a/supervisor/session/rtu.lua b/supervisor/session/rtu.lua
index 30844dd..fd30fd0 100644
--- a/supervisor/session/rtu.lua
+++ b/supervisor/session/rtu.lua
@@ -52,7 +52,7 @@ rtu.new_session = function (id, in_queue, out_queue, advertisement)
     local _parse_advertisement = function ()
         self.units = {}
         for i = 1, #self.advert do
-            local unit = nil
+            local unit = nil    ---@type unit_session
 
             ---@type rtu_advertisement
             local unit_advert = {
@@ -133,7 +133,7 @@ rtu.new_session = function (id, in_queue, out_queue, advertisement)
         -- process packet
         if pkt.scada_frame.protocol() == PROTOCOLS.MODBUS_TCP then
             if self.units[pkt.unit_id] ~= nil then
-                local unit = self.units[pkt.unit_id]    ---@type rtu_session_unit
+                local unit = self.units[pkt.unit_id]    ---@type unit_session
                 unit.handle_packet(pkt)
             end
         elseif pkt.scada_frame.protocol() == PROTOCOLS.SCADA_MGMT then
diff --git a/supervisor/session/rtu/boiler.lua b/supervisor/session/rtu/boiler.lua
index 8804bda..78931ec 100644
--- a/supervisor/session/rtu/boiler.lua
+++ b/supervisor/session/rtu/boiler.lua
@@ -79,7 +79,7 @@ boiler.new = function (session_id, advert, out_queue)
         }
     }
 
-    ---@class rtu_session_unit
+    ---@class unit_session
     local public = {}
 
     -- PRIVATE FUNCTIONS --
diff --git a/supervisor/session/rtu/emachine.lua b/supervisor/session/rtu/emachine.lua
index 340315e..b6c89b6 100644
--- a/supervisor/session/rtu/emachine.lua
+++ b/supervisor/session/rtu/emachine.lua
@@ -58,7 +58,7 @@ emachine.new = function (session_id, advert, out_queue)
         }
     }
 
-    ---@class rtu_session_unit
+    ---@class unit_session
     local public = {}
 
     -- PRIVATE FUNCTIONS --
diff --git a/supervisor/session/rtu/turbine.lua b/supervisor/session/rtu/turbine.lua
index 23c3d61..ccca068 100644
--- a/supervisor/session/rtu/turbine.lua
+++ b/supervisor/session/rtu/turbine.lua
@@ -75,7 +75,7 @@ turbine.new = function (session_id, advert, out_queue)
         }
     }
 
-    ---@class rtu_session_unit
+    ---@class unit_session
     local public = {}
 
     -- PRIVATE FUNCTIONS --