diff --git a/VAST 4.1 Samples/Viewable_Impression-test.xml b/VAST 4.1 Samples/Viewable_Impression-test.xml
index dba6b6f..0a043ef 100644
--- a/VAST 4.1 Samples/Viewable_Impression-test.xml	
+++ b/VAST 4.1 Samples/Viewable_Impression-test.xml	
@@ -1,7 +1,7 @@
 <VAST version="4.1" xmlns="http://www.iab.com/VAST">
   <Ad id="20010" sequence="1" conditionalAd="false">
     <Wrapper followAdditionalWrappers="0" allowMultipleAds="1" fallbackOnNoAd="0">
-      <AdSystem version="4.0">iabtechlab</AdSystem>
+      <AdSystem version="4.1">iabtechlab</AdSystem>
       <Error><![CDATA[https://example.com/error]]></Error>
       <Impression id="Impression-ID"><![CDATA[https://example.com/track/impression]]></Impression>
       <ViewableImpression id="1543">
@@ -30,4 +30,4 @@
       </VASTAdTagURI>
     </Wrapper>
   </Ad>
-</VAST>
\ No newline at end of file
+</VAST>