2 URL's same page (Wordpress, no external redirect)

Question

I've seen this question before in other topics, but it's not working for me, unfortunately... The thing is that I need to access the same page from 2 URL's:

http://website.com/product/productname

AND

http://website.com/product/productname/buy.html

There should be no external redirect, just open the same (first) URL when trying to open second one.

Website is Wordpress based.

Answer 1

Here this should work:

RewriteEngine On
RewriteRule /test/secondpage/ /your-first-page.html [L]

You have to save this as a .htaccess file

If not, search on google, there more solutuions than here