diff --git a/Images/zubaxgnss-v1.prototype b/Images/zubaxgnss-v1.prototype
index ea1de8772f..46d8c45f87 100644
--- a/Images/zubaxgnss-v1.prototype
+++ b/Images/zubaxgnss-v1.prototype
@@ -7,6 +7,7 @@
     "summary": "ZUBAXGNSSv1",
     "version": "0.0",
     "image_size": 0,
+    "image_maxsize": 253952,
     "git_identity": "",
     "board_revision": 0
 }