This page shows the HTTP Headers sent to it:
Connection: close
Accept: */*
Host: selectpdf.com
Referer: http://selectpdf.com/demo-vb/view-http-headers.aspx
User-Agent: Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)