The TACX Direct Drive Body SRAM/Shimano is specifically designed for use with the Neo 2 and Flux trainers, featuring a 12mm internal diameter axle hole. This freehub body allows for seamless compatibility with SRAM and Shimano drivetrains, ensuring smooth and efficient power transfer during your indoor cycling sessions. Its durable construction guarantees longevity, making it an essential component for serious cyclists looking to enhance their training experience. Easy to install and replace, this product is a reliable choice for any Tacx trainer setup.