diff --git a/furi/core/thread.h b/furi/core/thread.h
index 022894ee..692f2a10 100644
--- a/furi/core/thread.h
+++ b/furi/core/thread.h
@@ -28,7 +28,7 @@ typedef enum {
     FuriThreadPriorityNormal = 16, /**< Normal */
     FuriThreadPriorityHigh = 17, /**< High */
     FuriThreadPriorityHighest = 18, /**< Highest */
-    FuriThreadPriorityIsr = 32, /**< Deffered Isr (highest possible) */
+    FuriThreadPriorityIsr = (configMAX_PRIORITIES - 1), /**< Deferred ISR (highest possible) */
 } FuriThreadPriority;
 
 /** FuriThread anonymous structure */