PTO and ATO or Different Ordering Environments,
PTO is Pick To Order: where it is assumed that
availability of stock is plenty , just pick and relese and ship for an order.
ATO is Assemble to Order : it is assuemed that,
availble of option class, all included/standard items/ and depending up on the Order the Assemblies are carried and shipped.
where it is expected that an order is booked for a predefined model item,