Introduced in 1969, Ira's concept car was a Original Hot Wheel. It was designed from the ground up in house at Mattel. The Twin Mill has become one of the most recognizable and popular Hot Wheels casting for generations, enough that a full-size replica of the car was created and displayed at autoshows. Early versions saw what is called "Cut Fenders". These adhere to the drawings Ira made. This is proclaimed to be a prototype. Many different colors do exist, Antifreeze, Orange, Red, Apple Green, Creamy Pink. File:0307sr milestones04 z.jpg This casting was made in the USA only.