Hi everybody. We are launching our product in the end of this year and to encourage people to "test fit" if our product fits in their homes, we are going to offer them a free "fitting tool" that they can order through our e-commerce.

I want to create a follow-up mail that if the person who ordered the free fitting tool didn't buy our main product within 10 days after receiving the fitting guide, to give them for example 10% extra discount on the main product.

How do you set the criteria in "marketing automation" to get all the people that bought product  X.