How do I use 2 diferent Add to Cart templates

[CapereSpiritum]

Hi I'm using these modules in an ecommerce site
Cart 1.8.4
Products 2.18.4

I know there are newer versions but I need the Attributes feature which is no longer available in the new version.

My Problem:
There is a 'Featured Product' top left which needs to have Price and Buy styled differently to the same items in the Detail Template.

I've created different Add to Cart templates with different CSS classes.

How do I call each template for its respective location.

I know I've to use addtocarttemplate="DetailCart" I just cannot see where it goes.

Anyone done this before?