Facemilling arbors come in various types, designed to suit different milling machines and applications. Common types include Morse taper, ISO NT, R8, SK, and BT arbors. Morse taper arbors are commonly used in smaller machines, ISO NT arbors are standardized for larger industrial machines, R8 arbors are often found in Bridgeport milling machines, SK arbors are used in high-speed applications, and BT arbors are known for their dual-contact design. These arbors are typically measured in millimeters (mm) or inches (in) for diameter and length.