Festo Compressed Air Pipe Silver Polyurethane 4mm x 50m PUN-H Series, 558278

This is a 4mm outside diameter polyurethane air pipe from Festo's PUN-H series, supplied as a 50m length in silver.

What the numbers mean

Outside diameter 4mm, inside diameter 2.6mm — the wall thickness that sets flow and bend radius. It runs at a maximum operating pressure of 10 bar and works down to -0.95 bar, so it covers vacuum lines as well as standard compressed air feeds.

Operating temperature is -35°C to +60°C, which suits most workshop and outdoor pneumatic runs without special heating or cooling considerations.

Why PUN-H over standard PUN tubing

The "H" stands for hydrolysis resistant — the material holds up where moisture is present, which is why Festo rates it for water applications alongside compressed air and vacuum. It's also food safe and FDA compliant, so it's a sensible choice for food industry pneumatics or clean room installs.

Fitting it

It's designed for push-in pneumatic fittings with a one-click connection — no tools or sealant needed at the joint. Check your fitting's stated tube diameter matches this 4mm OD before ordering connectors.

Compliance

Manufactured from 100% polymer (no copper, no PTFE), it conforms to RoHS and meets ISO 8573-1:2010 compressed air quality classification.