This is a nut block that is designed to work with 8mm metric acme lead screws, which are commonly used for CNC and 3D printer applications. The nut block has a pitch of 2mm and a lead of 8mm, which means it moves 8mm for every rotation of the screw. The nut block also has a screw and nut mechanism that allows you to adjust the backlash, which is the amount of play or slop between the nut and the screw. The backlash adjustment can improve the precision and repeatability of your linear motion. The nut block can be mounted on plates or V-Slot using M5 screws and nuts or tee nuts. The nut block is made of delrin, which is a durable and self-lubricating material. The nut block is compatible with OpenBuilds lead screws and other similar lead screws. This nut block is a great choice for any project that requires smooth and accurate linear motion.