Can I use Products URL instead of Larger Image option?

[kobra]

I have written my own product pages and would like for my customers to be able to click on the image within the catalog and be redirected to /my-domain.com/productxyz.html page on my website. (They will still have to return to the zencart catalog to make a purchase, this is only for informational purposes.)

What you are seeking will most likely break the process/session control.
ZenCart is not designed to be used in this manner

The url that you have seen to be entered is a manufacures site url and is coded to open in a new window

[stevesh]

The URL specified in the product setup page will display on the product info page if the option in Admin - Catalog - Product Types - Edit Layout is set to do so. The link will open in a new window or tab.

As kobra said, switching the visitor between Zencart and non-Zencart pages can cause sessions problems, especially if your visitors will spend longer periods of time away from Zencart.