Offtoa's goal is to produce pro forma financial statements for you that of sufficient enough detail for investors and lenders. Here is what Offtoa does with these two numbers:

1. Offtoa adds the two numbers together and assumes this is the lead time required for purchasing raw materials before a customer purchase.
2. Once revenues are computed based on your assumptions, Offtoa uses this lead time to determine:
   1. When raw materials need to be purchased
   2. When the company must pay for raw materials (the above date plus payment terms you've negotiated with suppliers)
   3. Inventory entries for the balance sheet and cash flow statement during the months between the raw material purchase date and the customer purchase date.

Related Question:

How do I change production days? How do I change days in inventory?