This SA Design Book is a valuable resource for those interested in high-performance differentials, axles, and drivelines. The book covers a range of topics related to these areas, making it a must-have for anyone looking to improve their vehicle's performance. With a focus on customization and fitting performance, this book is perfect for those who want to take their vehicle to the next level. The manufacturer part number is SA170, and it is compatible with a variety of different repair manuals and literature. Whether you're a professional mechanic or a DIY enthusiast, this book is sure to provide you with the information you need to succeed.