This optional 14 inch extension arm is 2 inch by 1 inch black powdercoated steel, and goes between the standard arm and head unit, not only raising the maximum height but also increasing the positioning possibilities by an order of magnitude. To illustrate the difference the extension arm makes, imagine your arm ending with wrist attached at elbow, and no forearm at all. The extension arm is like adding that forearm back. Your Black Magic gets another joint, and another pivoting segment.