CheeMuii Brass DOT Push‑Lock Air Line Fittings Kit 23‑Piece (1/4", 3/8", 1/2") with Tube Cutter, CA360 Brass

This kit supplies 23 pieces designed to speed up installation and maintenance of vehicle air lines. Crafted from CA360 brass and conforming to DOT FMVSS 571.106 and SAE J1131 guidance, the fittings are corrosion resistant and rated for a broad temperature and pressure range. The assortment covers 1/4", 3/8" and 1/2" tubing so you can match common DOT copper or compatible plastic air lines without hunting parts.

What exactly is included and why those sizes matter?

The set contains 8 of 1/4" straight unions, 8 of 3/8" straight unions, 6 of 1/2" straight unions, plus a compact tube cutter. Those three diameters are the most frequently used in DOT-approved air brake and suspension systems, making the kit versatile for trucks, RVs, trailers and equipment.

• 8 × 1/4" straight union fittings for smaller control lines
• 8 × 3/8" straight union fittings for mid-size airline connections
• 6 × 1/2" straight union fittings for main airline runs
• 1 × tube cutter to trim tubing cleanly on the job

How do these push‑to‑connect fittings simplify repairs?

Installation is tool‑light: insert the prepared tube into the fitting until it seats and it seals. To remove, depress the release collet and pull the tube out; this makes field swaps and troubleshooting quicker without soldering or threaded adapters.

• Push‑lock design eliminates time‑consuming threading or brazing
• Removable fittings reduce downtime for replacements or reroutes
• Tube cutter included for clean, square cuts that ensure secure seals

Are these fittings durable enough for vehicle air systems?

Yes—the CheeMuii fittings are machined from CA360 brass for low permeability and good ductility in temperature extremes. They meet DOT and SAE-related standards commonly referenced for air brake components and hold up under typical operating ranges for road vehicles.

• CA360 brass construction for corrosion resistance and longevity
• Rated for vacuum up to 300 psi working pressure
• Serviceable between -40°F and +200°F (-40°C to +93°C)

Which applications are these unions best suited for?

Use this kit wherever DOT‑style airline fittings are needed: truck and trailer brake lines, RV air suspension plumbing, workshop compressor lines using DOT copper, and on-site emergency repairs. They’re also useful for general-purpose pneumatic plumbing in industrial or lawn equipment settings.

• Truck and trailer air brake and suspension repairs
• RV air systems and trailer hookups
• Workshop pneumatic setups and mower/tow equipment maintenance
• Field leak repairs and temporary reroutes

Who is this for? The CheeMuii 23PCS Brass DOT Air Line Fittings Kit is intended for mechanics, fleet technicians, RV owners, and DIYers who service air brake or suspension systems and need a compact, standards‑minded assortment. If you work with DOT copper tubing or compatible pneumatic lines and want a ready set of push‑to‑connect unions plus a tube cutter for on‑vehicle troubleshooting or maintenance, this kit is built to keep repairs fast and repeatable without specialty tools.