【Yu-packet shipping】 is used. Delivery is available on Saturdays, Sundays, and national holidays. Please purchase this if you are in a hurry. This is a static discharger. Compatible screw size is M6. It's a popular tune on sites like 【Minkara】. It is said that by discharging static electricity accumulated on the car body with this device, the car's original performance is brought out. Please use it by tightening it together with screws in the engine room, etc. When using, it seems that the maximum effect is achieved by unraveling the flat braided copper wire.