@TTRACY I m not sure of the scenario that you are trying to handle, if it was an inventory part setting Purch UoM, Inv UoM with conversion factor of 2 would be a solution. I think this is what you mentioned.

Is it possible to check the Quantity against the Standard Pack Size as the PO Line is updated? A custom event to check the Qty in PO Line against the Standard Pack Size.

eg: Qty % Standard Pack Size = 0 (% - modulus)

Because AFAIK, there is no out-of-box feature to increase the Qty of the PO Line in steps of 2.

Min Order Qty raises a warning message only and Standard Pack Size is not enforced when creating a PO line. As this is a non-inventory part, supplier schedules are not relevant. IMO this approach should work.

May be an expert can confirm the availability of such feature, if there is no such feature available, this would be a really useful idea to propose.

Hope this helps !

@TTRACY if you are using MRP for planning your supplies, then you have the option of setting Multiple Lot Size and then MRP will always create your Purchase Requisition lines as a multiple of 2. 

@TTRACY oups, please disregard my last reply. I just re-read your post and noticed that you’re using Non Inventory Purchase Part. So, MRP will not help in such case.