What's Wrong with my .htaccess code?

I am trying to get my links to redirect to something a little more search engine friendly but for some reason I am getting a 404 error. What's wrong with this code?

Redirect 301 /default.htm http://www.site.com/index.htm
Redirect 301 /links.htm http://www.site.com/links/links.htm
ErrorDocument 404 http://www.site.com/404.htm
RewriteEngine on
RewriteRule ^products_2\.htm$ /2/keyword.htm
RewriteRule ^products_3\.htm$ /3/keyword.htm
RewriteRule ^products_4\.htm$ /4/keyword.htm
RewriteRule ^products_5\.htm$ /5/keyword.htm
RewriteRule ^products_6\.htm$ /6/keyword.htm

Code (markup):

Thanks for your help

 

Why use mod_rewrite, just use

Redirect 301 /products_2.htm /2/keyword.htm

 

Because /2/keyword.htm doesn't exist, it's a fake directory and a generated keyword.

 

That's why you are getting 404s -- /2/keyword.htm doesn't exist. It should be the other way around, first what to rewrite, then what to rewrite it into.

So, RewriteRule /2/keyword.htm$ /products_2\.htm

So, if you type /2/keyword.htm in your browser, the server is going to show products_2.htm