Tax applies to the sale of manufacturing aids such as dies, patterns, jigs and tooling used in the manufacturing process notwithstanding the fact that the property used in manufacturing may subsequently be delivered to or held as property of the person to whom the manufactured product is sold. If the contract of sale between the manufacturer and the customer provides that title to the manufacturing aid passes to the purchaser prior to physical use of the property in the manufacturing process, then the manufacturing aid or its raw materials, if the manufacturing aid is fabricated by the manufacturer, may be purchased for resale. Tax then applies, unless otherwise exempt, to the sale of the manufacturing aid by the manufacturer to the customer, and not also with respect to the sale to the manufacturer. If the contract provides that title to the manufacturing aid passes to the customer in this state prior to use, then a retail sale subject to tax occurs in this state even though the manufacturing aid may subsequently be shipped to a point outside this state.