When viewing products details pages, you will notice a section called "components." Here you can click to create, edit, or link child components to a parent item. Each child component has a different set of fields which are all factored into the price calculator for the parent item when calculating costs. If you change the cost of any component #s that are linked to a parent item, the parent item bill of material will change the calculation for the rolled up cost at the parent level product as well. You can make changes to child components from within the parent item product details or when viewing the child component product details separately.