This price is for 5 pieces. The material is made of titanium alloy Ti-6Al-4V, also known as 64 titanium. It is extremely lightweight and will not rust, so it is made with a wide range of materials such as space and aviation industries, so you can use it with confidence. Made of 64 titanium. The screws are forged, then rolled and the head is forged, and then precision cut. Therefore, it is good to hold the tool and the head part will be much less deformed. While changing bolts to titanium are not a lot of performance improvements, they are not damaged by replacing them for rust resistance, durability and strength. ★Caution: Please make sure to tighten the bolt within the prescribed torque. We do not know the regulations torque by the vehicle, so please be sure to check service manuals for each car model. When attaching to aluminum products, please make sure to use anti-sheath or thread compound to prevent biting.