|Index||-||FAQ - Cart Help Buttons - Button Builders - "Add Cart" code - Create Special Properties (Size, Color, etc)|
When a shopper selects an option you can append a new piece to the end of the part number.
That way if you have a group of T-Shirts with a part number of "shirt001" you can then make a set of options to handle product sizes. And still maintain inventory for each individual size.
Your part numbers would end up looking something like this (you can use any value on the end you wish, this is just and example)