Ri-D. Forged extra-super duralumin 1-piece wheel One Piece Forged Aluminum Wheels. Produced by BBS-Japan using a special 7000 series alloy that helps make this wheel as light and strong as possible. An ultra-light design that realizes the ideal of light and sporty driving One look at this wheel with its 5 minimalist cross spokes makes two things clear: it’s ultra-lightweight, and it promises sporty driving. In fact, this is the wheel that BBS introduced in 2011 as the world’s first extra-super duralumin wheel.* Duralumin is an aluminum alloy that’s impressively strong and durable, and extra-super duralumin is even more so, finding use as an aerospace material. This design employs this advanced material to full effect. Application: BMW M3（G80）*（front only) BMW M4competition（G82）*（front only）