RewriteEngine On

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d

RewriteRule ^products$ products.php [L]
RewriteRule ^categories$ categories.php [L]
RewriteRule ^offers$ offers.php [L]
RewriteRule ^about$ about.php [L]
RewriteRule ^contact$ contact.php [L]
RewriteRule ^quote$ quote.php [L]