This is a muffler earth product, known for improving fuel efficiency and increasing torque. With gasoline prices remaining high, it's recommended for those who want to improve fuel economy, whether for driving, leisure trips, visiting family, daily commutes, or shopping! Lengths: Approximately 30 cm and approximately 25 cm (Please allow for a few millimeters of error) Terminal size: 8mm (Suitable for M8 bolts) This is a set of 4, including a set of 25cm and 30cm, and a set of two 30cm cables. Muffler earth is popular as an easy tuning option because it's easy to install and can be expected to improve fuel efficiency and torque. You can also install it on the muffler side using metal bands for hoses, etc., so it fits a wide range of vehicles. (Bands are not included, so you will need to prepare bands separately if you use them for installation) ⚠ Although it can be installed on various vehicles, please research the compatibility, the required cable length, and the actual installation yourself. Instructions are not included. ⚠ To maximize the effect of the muffler earth, please remove rust, dirt, and paint from the installation area and ensure that the metal part and the terminal are in contact during installation.