Outside diameter: 1"/25.4mm Inside diameter: 1/2"/13mm (fits 1/2" or M12 bolts) Length: Varies-Choose Length Shape: Round Material Type: T-6061 Aluminum with tumbled aluminum finish Material: All of our unthreaded aluminum spacers and standoffs are made from quality aluminum alloy, which provides excellent strength, durability, and corrosion resistance. Heat Dissipation: Aluminum Spacers/bushings have good thermal conductivity, allowing it to efficiently dissipate heat from electronic components. Metal Spacers Online provides a number of aluminum spacer sizes and materials for home improvement, DIY, automotive, industrial and manufacturing applications. You are sure to find the metal spacer that you need from our Amazon Store. Many Available Sizes: Our aluminum spacers come in various diameters and lengths to accommodate different application requirements, please select the correct option from the menu that will meet your requirements. Other Metal Spacer Options: This aluminum spacer may also be available with a black anodized finish or in high quality mild steel material, please check our Amazon Store for other options. Metal Spacers Online provides many sizes of round aluminum spacer, bushings, standoffs and washers. Our aluminum spacers are either milled or extruded for a quality smooth finish. Before checking out, choose the length of spacer and the package quantity to insure you are getting what you need. This listing is for a specific inside and outside diameter, you can visit our Amazon store to browse all of our other sizes that are available, you are sure to find what you need there.