Insulated Ring Terminals are electrical connectors designed to securely attach wires to screw or stud type connections. They consist of a metal ring or tongue that is crimped or soldered to the end of a wire, and this metal part is then covered with an insulating material.
  
Features:
Secure Connection: The ring shape provides a reliable and captive connection, preventing accidental disconnection, especially in environments with vibration.   
Insulation: The insulating sleeve, typically made of vinyl, nylon, or heat-shrink material, covers the crimped or soldered area. This prevents short circuits, protects against electrical shock, and can offer environmental protection against moisture and corrosion.   
Variety of Sizes: Insulated ring terminals come in a wide range of sizes to accommodate different wire gauges (AWG or metric) and stud/screw sizes (metric or imperial).
Color Coding: Often, the insulation is color-coded to indicate the appropriate wire gauge range for the terminal.   
Applications: They are commonly used in automotive, marine, industrial, and household electrical wiring for making secure and insulated connections to components like circuit breakers, terminal blocks, grounding points, and electrical equipment.
  
In essence, insulated ring terminals offer a safe, secure, and organized way to terminate wires onto screw or stud connections in various electrical applications