Description

Overview

The 1/4 air brake push-in double union joins two matching sections of imperial nylon tube in a straight line. It provides a compact repair connection where a damaged tube section must be replaced or two 1/4″ air lines need to be joined without threaded adaptors.

Features

• Equal push-in connections for 1/4″ outside-diameter nylon tube
• Straight tube-to-tube configuration without threaded ports
• Brass one-piece body with an integrated collet and seal at each end
• Reusable connection allows tube removal after depressurising the system

Specifications and Materials

This brass double union accepts 1/4″ imperial air-brake tube at both ends. Each push-in port grips and seals the tube without separate compression nuts, olives or inserts. The reduced centre section provides a clear visual break between the two equal connections. Part number: 88-004-04.

See the official brass push-connect air brake fitting guide

Compatibility and Fitment

Confirm that both air lines measure 1/4″ across the outside diameter. Do not substitute 6mm metric tube, a reducing union or a bulkhead union, as these fittings use different dimensions or installation arrangements.

Cut both tube ends square and remove burrs before pushing each line fully into the internal stops. Pull back lightly on both tubes to confirm engagement. These cross-references show where this part replaces the part numbers and applications listed. Some installations may need minor changes. Dq62dot04, 35-6204, 356204, AQ62-DOT-4, AQ62DOT4, 1862X4, 3106 56 00DOT, 31065600DOT

Compliance and Safety

Depressurise the complete air circuit before cutting the tube, fitting the union or releasing either collet. Inspect the tube around each sealing point for scoring, flattening, contamination or heat damage. A worn tube surface can leak even when inserted to the correct depth.

Keep the repaired line free from tension, sharp bends and contact with moving or hot components. Repressurise the system gradually and leak-test both ends of the union before returning the vehicle to service.

Trailer Applications

Workshops use this straight joiner for local repairs to 1/4″ air-brake, air-suspension and auxiliary pneumatic lines on trucks and trailers. Its slim centre section also suits confined tube runs where a tee, elbow or threaded connector would add unnecessary bulk.

Cross-reference and Suitability

This part cross-references to or suits the following equivalent part numbers and compatible alternatives:

Why Choose ICS Trailers

ICS Trailers supplies straight unions and matching elbows, tees and connectors for heavy vehicle air-line repairs. To confirm the correct size, send a clear photo of the old fitting and measure the outside diameter of the nylon tube.

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