Smc Pneumatics KQ2H04-00A Union Straight Tube Fitting

Product Description

The SMC PNEUMATICS KQ2H04-00A is a push-to-connect union straight tube fitting designed for pneumatic and fluid transfer systems. It provides a tool-free inline connection between two tube segments of equal outside diameter. The fitting is constructed from brass with polybutylene components and is rated for a maximum working pressure of 145 psi. With an overall length of approximately 1.09 inches (27.60 mm) and a tube outside diameter of approximately 0.16 inches (4.00 mm), it is suited for compact plumbing and pneumatic assemblies. Installation and removal require no threading or wrenching, making it a practical choice for technicians who service high-cycle or tight-access pneumatic lines.

This fitting is used in pneumatic control systems, light industrial fluid lines, and instrumentation tubing. It is well suited for residential and light commercial automation panels, compressed air distribution manifolds, and other low-to-medium pressure pneumatic circuits. The push-to-connect design is commonly used by HVAC controls technicians, pneumatic system installers, and industrial maintenance professionals working with small-bore tubing in confined spaces. The operating temperature range of 23 degrees F to 140 degrees F covers most indoor climate-controlled and light-industrial environments.

Key Features

• Push-to-connect design allows fast, tool-free tube insertion and secure locking
• Straight union configuration joins two tube ends in-line without bends or offsets
• Rated to 145 psi maximum working pressure for pneumatic service
• Brass body with polybutylene construction for corrosion resistance in pneumatic circuits
• Compact overall length of approximately 1.09 inches suits tight-clearance installations
• RoHS compliant

Compatibility

Designed as an OEM-style push-to-connect union fitting for pneumatic tubing with a 4.00 mm outside diameter, typical in small-bore pneumatic and fluid control systems.

Installation Notes

Installation is performed by a qualified pneumatic systems technician or HVAC controls specialist. Depressurize and isolate the pneumatic circuit fully before disconnecting or inserting any fitting. Ensure tube ends are cut cleanly and squarely, and that tubing outside diameter matches the fitting specification before inserting. When releasing the tube, depress the collet release collar evenly to avoid damage to the internal locking mechanism.