Smc Pneumatics KCL04-99 Push-to-connect Plug Fitting

Product Description

The SMC PNEUMATICS KCL04-99 is a push-to-connect tube fitting plug designed to seal off an open port or tube end in pneumatic and fluid-handling systems. Constructed with a brass body and polybutylene components, it handles working pressures up to 145 psi. The plug accepts a 4 mm outside-diameter tube and is installed without tools by pressing the tubing directly into the fitting. Licensed plumbers, pipefitters, and pneumatic system technicians are the primary installers in both industrial and light commercial environments.

This fitting is suited for use in compressed-air distribution lines, pneumatic control circuits, and low-pressure fluid systems where a tube run needs to be capped or an unused port needs to be blocked. Its push-to-connect design makes it practical for tight-access installations where threaded or barbed alternatives would require additional tooling. The 4 mm tube OD is a standard metric sizing common in instrumentation, OEM equipment, and pneumatic manifold assemblies.

Key Features

• Push-to-connect design requires no tools for installation or removal
• Rated to 145 psi maximum working pressure
• Compatible with 4 mm outside-diameter tubing
• Brass and polybutylene construction for durability in pneumatic service
• Compact plug configuration seals open ports or tube ends

Compatibility

Designed as an OEM-style replacement or service fitting for pneumatic systems using 4 mm outside-diameter push-to-connect tubing rated for service up to 145 psi.

Installation Notes

Depressurize and isolate the pneumatic or fluid line completely before installing or removing this fitting. Verify that the tubing outside diameter is exactly 4 mm and that the tube end is cut cleanly and squarely to ensure a proper seal. Push-to-connect fittings should be installed in accordance with the equipment manufacturer guidelines and applicable codes such as the Compressed Air and Gas Institute standards for pneumatic systems. Inspect the fitting for leaks after restoring system pressure.