Ailbiuko 53PC Brass DOT Air Brake Line Compression Straight Unions — CA360 Brass, PTFE Tape

This 53-piece Ailbiuko brass DOT straight union kit supplies DOT-compliant compression fittings and ferrules for joining air brake tubing securely.

The Ailbiuko 53PCS Brass DOT Air Brake Line Compression Fittings Straight Union is a full assortment designed for repairing and extending air brake lines and other pneumatic copper tubing systems. Built from CA360 brass to meet DOT FMVSS 571.106 standards, the kit includes multiple union sizes, ferrules and a roll of PTFE tape so you can complete most common in-line joins without sourcing extra parts.

What sizes and parts are included in the kit?

The kit contains a broad selection of straight union fittings and the matching sleeves needed for compression connections. It covers small to larger brake tube diameters to fit many vehicle and equipment applications.

• 4 × 1/8" × 1/8" straight unions
• 6 × 1/4" × 1/4" straight unions
• 6 × 3/8" × 3/8" straight unions
• 2 × 1/2" × 1/2" straight unions and 1 × 5/8" × 5/8" union
• 34 ferrule sleeves and 1 roll of PTFE (Teflon) tape included

How durable are these fittings under operating conditions?

Ailbiuko manufactures these unions from CA360 brass for corrosion resistance and high-temperature performance suited to air brake environments. They withstand a wide working temperature span and are rated for typical pneumatic pressures used in brake systems.

• Material: CA360 brass, resistant to corrosion and wear
• Pressure tolerance: up to approximately 300 PSI under normal conditions
• Temperature range: approximately -65°F to +200°F (follow tubing maker limits)

How do I install the compression straight unions?

Installation is straightforward: slide the ferrule over the tubing, insert the tube into the union, then tighten the nut to compress the sleeve. Using a wrench in confined spaces will ensure a secure, leak-minimizing connection; the included PTFE tape helps improve seal integrity on threaded joins.

• Prepare tubing: cut square and deburr before assembly
• Fit sleeve then insert tubing fully into the union body
• Tighten with appropriate wrenches and add PTFE tape on threaded areas

Where can I use these straight union fittings?

These unions are intended for air systems that use copper or compatible tubing and are commonly applied across automotive and light industrial pneumatic tasks. They are suitable for repair, replacement or custom plumbing of brake and air-operated components.

• Automotive and truck air brake line repairs and extensions
• Air horns, gauges, and seat-operating air systems
• Workshop pneumatic lines, towing equipment, and lawn mower air controls

Who is this for: Technicians, DIY mechanics, fleet maintenance crews and hobbyists who need a comprehensive set of DOT-compatible straight union compression fittings will find this Ailbiuko kit useful. It saves time sourcing multiple sizes by bundling commonly used unions, ferrules and sealing tape, making on-vehicle repairs and shop plumbing faster and more reliable. Always verify tubing compatibility and follow vehicle manufacturer specifications when servicing air brake systems.