Low-Pressure Hose Tail – UNO Male – Straight – Crimp-On

A low-pressure UNO (SAE O-ring boss) male on a straight crimp tail, for O-ring boss ports on return and drain lines.

Mild steel body with a plated finish, manufactured to the standard listed above.

This is the tail only – clamps are sold separately

Low-pressure tails are not crimped. They push into the hose and are held with a worm drive clamp over the barb. There is no ferrule and no crimp diameter to set.

• Cut the hose square and push it fully onto the barb, past the last serration.
• Position the clamp over the barbed section, not over the plain shank behind it.
• Nip it up until the hose swells slightly between the serrations. Over-tightening cuts the cover and starts a leak path.
• Two clamps on larger bores, spaced along the barb, on suction and return lines that see vibration.

Watch: How to Identify Hydraulic Hose Fittings and Hydraulic Adaptors JIC and BSP

Thread Standards

• SAE O-Ring Boss Male (UNO/UNF) – SAE J1926 / ISO 11926 straight thread O-ring boss, seals on an O-ring squeezed against the port spotface, not on the thread

How to Choose

• A straight tail is the default. Only go to a bend when the hose would otherwise leave the port at an angle it does not like.
• Low-pressure duty only.
• Seals on an O-ring that squashes into the port face, not on the thread.

Technicians Advice

Check the O-ring is seated and undamaged before you start the thread. A UNO O-ring that rolls or nips on the way in leaks straight away, and you cannot see it once the fitting is home.

Where You’ll Find It

• SAE O-Ring Boss Male (UNO/UNF) – Cylinder end caps, pump and valve bosses on US-built plant. Common on Australian-assembled cylinders too, where it is usually called UNO.

Cross-Reference

• SAE O-Ring Boss Male (UNO/UNF) – SAE J1926 / ISO 11926 straight thread O-ring boss. Also written ORB, SAE ORB or UNO. Thread form is UN/UNF.

Parker, Gates, Aeroquip and Ryco all manufacture to these same standards under their own part numbering, so a fitting built to the standard above will mate with theirs.

Cross-references are given at series level as a guide to the standard, not as a part-for-part substitution. Always confirm the thread form, size and seal type against the port before ordering.

What “low pressure” means here

• These tails are built for the low-pressure side of a system – return lines, case drains, suction lines and tank lines.
• They are not a substitute for a braided-hose pressure tail. If the line sees pump pressure, use a two-piece tail on 1‑wire or 2‑wire hose instead.
• The working pressure of the finished assembly is set by the lowest-rated part in it – usually the hose. Check the hose rating and match the tail to it, not the other way round.
• Suction and return lines run at low pressure but move a lot of oil. Size on bore and flow, not on the thread you happen to have spare.

Downloads

📄 Thread Identification Chart (PDF)

Same Threads, Other Angles

🔗 90° Compact – same threads

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Ayrtec two-piece crimp-on hose tails, stocked and dispatched by Hydraulic.Online.

Need a hand? Call 1300 146 737 or email sales@mhfgc.com.au – real technicians, real answers.