CS-Cart "Stock filter" add-on is a good solution for online store owners who don't hide out-of-stock products. This add-on adds a Show out of stock/Hide out of stock button on a category page in the storefront allowing both registered and unregistered customers to hide out-of-stock products from viewing.
For the correct add-on functioning, please make sure that you checked the Show out of stock products checkbox in the Settings -> General (the admin back end).
The add-on works correctly in Internet Explorer 7/8/9, Mozilla Firefox, Safari, Google Chrome and Opera latest browser versions.
The add-on is compatible with CS-Cart v.4.