Need help setting up a promotion

If a customer purchases $75 worth of knobs of certain brand, I want to offer free shipping on the knobs only and not anything else in the cart.



I have “brand” set up as a feature, so that's at least something. As to the rest of it, I really don't see a whole lot of options that will parse out the requirements stated above.



Ideas?

We have a custom mod done for this to limit the cart products and the selected products subtotal instead of the whole cart products subtotal. Please feel free to contact us for more details.