diff --git a/application/forms/SimulationForm.php b/application/forms/SimulationForm.php
index 938ffaf..04a0f56 100644
--- a/application/forms/SimulationForm.php
+++ b/application/forms/SimulationForm.php
@@ -12,7 +12,7 @@ class SimulationForm extends BpConfigBaseForm
     /** @var MonitoredNode */
     protected $node;
 
-    /** @var MonitoredNode */
+    /** @var ?MonitoredNode */
     protected $simulatedNode;
 
     /** @var Simulation */