It currently provides a 9% taxdeductionfrom net income for businesses engaged in "qualified production activities" in the U.S. Those activities include manufacturing a product, selling, leasing or licensing it, and engineering and software activities related to that production.
About 40% of that revenue would be a result of not extending the 2001-03 tax cuts for high-income households and another 30% would come from the deduction cap (so you could wipe that off the books already).