I have a product at ebay which has only one VariationSpecifics(size). but when i use getItem for the same product it return me two VariationSpecifics. check the response. [VariationSpecifics] => stdClass Object ( [NameValueList] => Array (  => stdClass Object ( [Name] => MPN [Value] => 15DB 8 )  => stdClass Object ( [Name] => Size [Value] => Size 8 ) ) ) why MPN variation specification is not appearing at ebay? why it is appearing at getItem product response ?