HRU06-0.25-06 Buna-N 80 U-Cup Seal 1/4" ID X 3/8" OD X 1/16" HT

Reliable Sealing for Compact Hydraulic Applications

If you need a small profile seal that still delivers dependable performance, this Buna-N U-Cup is a solid choice. Designed for compact hydraulic systems, it provides consistent sealing while keeping friction low and installation simple.

Built from 80 durometer Buna-N (NBR), this seal offers a strong balance of flexibility and durability. It performs well in oil-based systems and is ideal for applications where space is tight but reliability still matters.

Operating temperature: -40° to +225°F (–40° to +107°C)

Material & Performance Details

This U-Cup follows a proven asymmetrical design that increases sealing effectiveness under pressure while helping protect against contamination.

• Material: Buna-N (NBR) N801B
• Durometer: 80 Shore A
• Color: Black

Performance strengths:

• Good resistance to petroleum-based oils
• Reliable sealing under pressure
• Low compression set for consistent sealing
• Good abrasion resistance for longer service life
• Compact profile for tight groove designs

Chemical compatibility:

Excellent resistance to:

• Petroleum-based oils
• Hydraulic fluids (mineral-based)
• Greases

Limited capability with:

• Water and water-glycol fluids
• Mild chemicals

Not compatible with:

• Strong acids
• Ozone and weathering
• Ketones and brake fluids

Sizes & Measurements

• Dimensions: 1/4" ID X 3/8" OD X 1/16" HT
• Actual: 0.248" ID X 0.374" OD X 0.059" HT
• Metric: 6.35 mm ID X 9.52 mm OD X 1.50 mm HT
• Part Number: HRU06-0.25-06
• Profile: N23 U-Cup
• Material Code: N801B

Applications & Use Cases

This compact U-Cup is ideal for:

• Small hydraulic cylinders
• Pneumatic and light-duty hydraulic systems
• Valves and actuators
• General industrial equipment

It works well where space is limited and consistent sealing is required without overdesigning the system.

Key Specifications

• Material: Buna-N (NBR)
• Durometer: 80 Shore A
• Color: Black
• Temperature Range: -40°F to +225°F (–40°C to +107°C)
• Design: Asymmetrical U-Cup (N23 profile)
• Pressure Capability: Application dependent

Why Buy from The O-Ring Store LLC

We focus on making sure you get the right seal the first time, without delays or confusion.

• ISO9001:2015 certified quality processes
• USA-based inventory for fast delivery
• Same-day shipping on in-stock items
• Full lot traceability available on request
• Technical support from a team that understands sealing
• Competitive pricing with consistent quality

We make getting O-Rings easy by keeping things clear, accurate, and fast.

Frequently Asked Questions

1. What is Buna-N best used for?
Buna-N is ideal for oil and fuel applications. It performs well in most standard hydraulic systems using petroleum-based fluids.

2. Can this U-Cup be used in pneumatic systems?
Yes, for light-duty applications. Always confirm pressure and lubrication requirements.

3. What does 80 durometer mean?
It refers to hardness. 80A is slightly harder than standard 70A, giving better wear resistance and extrusion control.