diff --git a/include/ntapi/nt_sync.h b/include/ntapi/nt_sync.h
index ecf5f0c..5b28833 100644
--- a/include/ntapi/nt_sync.h
+++ b/include/ntapi/nt_sync.h
@@ -128,7 +128,7 @@ typedef union __attr_aligned__(NT_SYNC_BLOCK_SIZE) _nt_sync_block {
 		int32_t		pid;
 		uint32_t	flags;
 		uint32_t	srvtid;
-		uint32_t	lock_tries;
+		int32_t		lock_tries;
 		uint32_t	ref_cnt;
 		uint32_t	busy;
 		int32_t		invalid;