Designed and manufactured myself. Made out of Delrin to help keep it cool on those hot days. Its kinda hard to tell in the photos but, its not your typical sphere shape. Instead of being completely round it has an angle on the underside to give a more organic grip. Check out he pix and let me know what you think! The material used is the same you will find in most other high quality shift knobs. They are CNC machined to fit with perfection. Currently I have not designed one for STI models.