Cost-Effective Solution: This set includes 8pcs SBR16 shaft collars and a wrench for set screws. Each collar has an inner diameter of 16mm, an outer diameter of 35mm, and a width of 12mm, offering and utility for various applications. Versatile Applications: Ideal for shaft fixing and positioning, these linear guide stops are perfect for DIY CNC machine tools. They are extensively used in industries such as medical equipment, food processing, mechanical and textile equipment, ensuring a high-quality choice for diverse machinery. Superior Craftsmanship: Crafted from high-quality aluminum alloy, these collars boast high hardness, anti-rust, and resistance. Easy Installation: Effortlessly slide the collar onto the shaft and secure it using the included wrench to tighten the screws. Designed to fully engage with the shaft, these collars provide strong locking force without causing damage to the shaft. The actual product may have slight color difference or difference, which will not affect the use Colour:Silver Material:Aluminum Alloy Package Contents: 8 x SBR16 Linear Rail Stop Collars 1 x Wrench Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.