Fore fuel Y blocks allow you to split one fuel line into two stainless steel braided AN lines. Unlike most blocks which Y and take up a lot of room, these split in parallel- giving you a much cleaner installation. Great Fore Precision Works quality, CNC machined from solid aircraft grade aluminum. Each block has one 1/2" and three 3/8" NPT threaded ports. Fittings are not included. Get one and add more fuel to your supercharger system.