※Price negotiations are not accepted. Details Brand: BONES WHEELS Model: X-FORMULA DOUBLE LOCKS Color: White Set of 4 (for one skateboard) Retail price: ¥9,680 (tax included) Size Diameter: 54mm Width: 34mm Contact patch: 21.5mm Hardness: 99A Shape: V7 About X-Formula X-Formula is an innovative wheel born from the BONES WHEELS factory. It's a wheel that rolls like a soft wheel on rough surfaces and slides like a hard wheel. Speed X-Formula is a very fast wheel due to its ultra-high rebound. Compared to other wheels, it absorbs vibrations and softens impacts, allowing you to roll smoother and faster on any surface. Grip & Slide X-Formula has slideability born from a unique blend of high-performance materials. It slides when you need it to and grips firmly when you need it to. This is because X-Formula has been specially formulated to handle all types of surfaces. Developed over 10 years, it has been fine-tuned to optimize performance and deliver the best results. X-Formula is a truly unique product. Durability X-Formula uses the highest quality, long-lasting materials, making it a smooth, fast, and durable wheel. It's a great value because it lasts a long time. It also softens landings and absorbs vibrations, reducing strain on your body and allowing you to skate longer. These wheels will change your life!