This 5/8" Air Brake Full Union is designed for use with nylon or copper air brake tubing, ensuring DOT compliance and meeting SAE J246 requirements. Its all-brass construction guarantees durability and reliability. Sold individually, this union fits most makes and models, making it a practical and versatile choice for air brake systems. With its high-quality features and compatibility, this product is an essential component for maintaining the safety and efficiency of your air brake system.