diff --git a/nx/include/switch/services/ns.h b/nx/include/switch/services/ns.h
index 43a1c966..fcead87d 100644
--- a/nx/include/switch/services/ns.h
+++ b/nx/include/switch/services/ns.h
@@ -92,8 +92,8 @@ typedef struct {
 
 /// SystemUpdateProgress. Commands which have this as output will return 0 with the output cleared, when no task is available.
 typedef struct {
-    u64 unk_x0;                    ///< Unknown.
-    u64 unk_x8;                    ///< Unknown.
+    s64 current_size;                  ///< Current size.
+    s64 total_size;                    ///< Total size, <=0 indicates that no progress is available.
 } NsSystemUpdateProgress;
 
 /// EulaDataPath