Build Your Very Own D-Shaped Steering Wheel with the GT Pro Hub The GT Pro Hub is ideal for custom-building your own steering wheel. It’s compatible with nearly all steering wheels with a diameter of 320 to 350 mm and, weighing just 1,250 g, features a pleasantly lightweight design. The hub is equipped with a total of 14 controls, 8 of which are customizable. The patented HALL paddle modules provide an authentic racing-style shifting feel.