This is a muffler earth cable, 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 activities, visiting family, commuting, or everyday shopping! Lengths: Approximately 30 cm and approximately 25 cm (Please allow for a few millimeters of error) Terminal size: 8mm (Suitable for M8 bolts) We also have 25 cm cables in stock, so we can accommodate changes to a combination of 30 cm and 25 cm. If you would like to change the combination, please leave a comment. Muffler earth cables are easy to install and are popular as a simple tuning option that can improve fuel efficiency and increase torque. The muffler side can be installed using metal bands for hoses, etc., so it can be used on various vehicle types. (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 vehicle types, please research the compatibility, required cable length, and actual installation yourself. Instructions are not included. ⚠ To maximize the effect of the muffler earth cable, please remove rust, dirt, and paint from the installation area and ensure that the metal part and the terminal are in contact during installation.