This Schaefer 2" in 51mm single aluminum block swivel shackle is a top-quality sailing hardware that is perfect for your sailing needs. It has a height of 4 inches and a width of 2 inches, making it a great choice for those who are looking for a reliable and durable shackle. This shackle is made from high-quality aluminum, which ensures that it is strong and long-lasting. It is compatible with a range of different boats and is easy to install, making it a great choice for anyone who wants to upgrade their sailing gear.