diff --git a/scripts/image_signing/make_dev_ssd.sh b/scripts/image_signing/make_dev_ssd.sh
index 458a37f0e4..7139c0d5ae 100755
--- a/scripts/image_signing/make_dev_ssd.sh
+++ b/scripts/image_signing/make_dev_ssd.sh
@@ -225,7 +225,7 @@ main() {
   # Make the root filesystem remountable if needed.
   if [ ${FLAGS_remove_rootfs_verification} = $FLAGS_TRUE ]; then
     local root_offset=$(partoffset "$FLAGS_image" 3)
-    enable_rw_mount "$FLAGS_image" "$root_offset"
+    enable_rw_mount "$FLAGS_image" "$((root_offset * 512))"
   fi
 
   resign_ssd_kernel "$FLAGS_image" || num_signed=$?