diff --git a/lib/scripts/pdf_a4_portrait.js b/lib/scripts/pdf_a4_portrait.js
index 414cfee..6367281 100755
--- a/lib/scripts/pdf_a4_portrait.js
+++ b/lib/scripts/pdf_a4_portrait.js
@@ -54,7 +54,7 @@ setTimeout(function () {
 // ----------------------------------
 page.onLoadFinished = function (status) {
   // The paperSize object must be set at once
-  page.paperSize = definePaperSize(getContent(page), options)
+  page.paperSize = options.paperSize || definePaperSize(getContent(page), options)
 
   // Output to parent process
   var fileOptions = {