Let's say you've got two tables that vary in terms of their finish, but they are the same price and you could swap between the two on your projects.
You can add the tabes as 'Alternates' to each other.
If you had someone on the phone who wanted to book one of the tables, but it was sold out, you'd be able to provide replacement suggestions at a glance.
On your projects, you'll also see Alternates as suggestions in case you are out of stock/ overbooked on the given item under Relations and Alternates. Just keep in mind that the system won't automatically add the alternate, but it will provide you with the suggestion when you click on the the three dots next to the item and then 'View Relations' button, or click the 'Relations' button next the the item's name on a contract.
(Above is an example of an alternate chair to the Folding Fruitwood Chair)