Built to keep service trucks working and repair shops profitable, the OSK™ Max Truck O-Ring Kit gives hydraulic service technicians the most common AS568, SAE Boss, and Flange O-Rings needed for fast field repairs. When a hydraulic hose fails, an ORB fitting leaks, or a flange connection needs resealing, having the right O-Ring on hand helps reduce downtime, prevent leaks, and complete more jobs per day.
This professional O-Ring kit includes 1,430 total black Buna-N O-Rings in both 70 Duro and 90 Duro. The Buna-N 70 sizes cover common AS568 standard sealing needs, while the Buna-N 90 Boss and Flange O-Rings provide extra hardness for higher-pressure hydraulic fittings where extrusion resistance matters. Less guesswork. Better coverage. Faster repairs.
Free Bonus Included: FN LUBE 2 oz General Purpose O-Ring Lubricant, an O-Ring pick, and an Olypsys® Pro-Grid, a $29.97 value.
Operating Temperature
Operating temperature: -40° to +250°F (–40° to +121°C)
Material & Performance Details
This kit includes Buna-N Nitrile 70 Duro black O-Rings and Buna-N Nitrile 90 Duro black O-Rings. Buna-N is the industry standard for petroleum-based hydraulic systems because it offers strong oil resistance, good abrasion resistance, and dependable compression set performance.
The 70 Duro O-Rings provide flexibility for common static and dynamic sealing. The 90 Duro Boss and Flange O-Rings provide added hardness for hydraulic fittings where pressure and extrusion resistance are important.
Excellent resistance to:
- Petroleum oils
- Hydraulic fluids
- Diesel fuel
- Gasoline
- Mineral oils
- Grease and lubricating oils
Limited capability with:
- Ozone exposure
- Sunlight / UV
- Mild acids
- Weathering
Not compatible with:
- Strong acids
- Ketones
- Glycol-based brake fluids
- Aromatic hydrocarbons
- Chlorinated hydrocarbons
Sizes & Measurements
Total Kit Count: 1,430 O-Rings
Material: Buna-N Nitrile
Color: Black
Standards Included: AS568, SAE Boss, Hydraulic Flange
Durometer Included: 70A and 90A
Box 1: AS568 -000 Series Buna-N 70 Duro O-Rings
1/16" CS O-Rings, dimensions listed on the AS568 O-Ring size chart
- AS568-006 through AS568-018: 25 pcs each
- AS568-019 through AS568-022: 20 pcs each
- AS568-023 through AS568-026: 15 pcs each
- AS568-028 through AS568-030: 15 pcs each
Box 2: AS568 -100 Series Buna-N 70 Duro O-Rings
3/32" CS O-Rings, dimensions listed on the AS568 O-Ring size chart
- AS568-109 through AS568-118: 25 pcs each
- AS568-119 through AS568-120: 20 pcs each
- AS568-121 through AS568-127: 15 pcs each
- AS568-128 through AS568-129: 10 pcs each
- AS568-131: 10 pcs
- AS568-133: 10 pcs
- AS568-135: 5 pcs
Box 3: AS568 -200 Series Buna-N 70 Duro O-Rings
1/8" CS O-Rings, dimensions listed on the AS568 O-Ring size chart
- AS568-210 through AS568-214: 20 pcs each
- AS568-215 through AS568-222: 15 pcs each
- AS568-223 through AS568-224: 10 pcs each
- AS568-226: 10 pcs
- AS568-228: 10 pcs
- AS568-232: 10 pcs
- AS568-236: 10 pcs
Box 4: SAE Boss Buna-N 90 Duro O-Rings
155 total Boss O-Rings in 8 common hydraulic fitting sizes
- AS568-903, SAE #3 Boss Fitting: 15 pcs
- AS568-904, SAE #4 Boss Fitting: 25 pcs
- AS568-906, SAE #6 Boss Fitting: 15 pcs
- AS568-907, SAE #7 Boss Fitting: 25 pcs
- AS568-908, SAE #8 Boss Fitting: 25 pcs
- AS568-910, SAE #10 Boss Fitting: 25 pcs
- AS568-912, SAE #12 Boss Fitting: 15 pcs
- AS568-916, SAE #16 Boss Fitting: 10 pcs
Box 5: Hydraulic Flange Buna-N 90 Duro O-Rings
45 total Flange O-Rings in 6 common hydraulic flange fitting sizes
- Flange Fitting #8: 10 pcs
- Flange Fitting #12: 10 pcs
- Flange Fitting #16: 10 pcs
- Flange Fitting #20: 5 pcs
- Flange Fitting #24: 5 pcs
- Flange Fitting #32: 5 pcs
Applications & Use Cases
The OSK™ Max Truck O-Ring Kit is built for hydraulic service trucks, mobile repair technicians, heavy equipment repair, agricultural machinery, construction equipment, fleet maintenance shops, and industrial maintenance departments.
This kit helps technicians seal ORB fittings, SAE Boss fittings, AS568 grooves, and hydraulic flange connections without losing time searching for common sizes. For the customer, the value is simple: fewer leaks, fewer return trips, and faster equipment repairs.
Key Specifications
- Material: Buna-N Nitrile
- Durometer: 70A and 90A
- Color: Black
- Standards: AS568, SAE Boss, Hydraulic Flange
- Temperature Range: -40° to +250°F (–40° to +121°C)
- Total Pieces: 1,430 O-Rings
- Standard AS568 O-Rings: 1,230 pcs Buna-N 70 Duro
- SAE Boss O-Rings: 155 pcs Buna-N 90 Duro
- Hydraulic Flange O-Rings: 45 pcs Buna-N 90 Duro
- Lubricant Included: FN LUBE 2 oz tube
- Tools Included: O-Ring pick and Olypsys® Pro-Grid
- Certifications: Lot traceability and documentation available on request
Why Buy from The O-Ring Store LLC
When you buy from The O-Ring Store LLC, you are not just buying a box of O-Rings. You are getting a kit built around real hydraulic repair needs, backed by a team that understands sealing problems and service truck downtime.
We are ISO9001:2015 certified, stock product in the USA for fast delivery, and ship in-stock items the same day when order requirements are met. We also offer full lot traceability, documentation on request, custom kit configurations, and experienced technical support when your team needs help finding the right seal.
We make getting O-Rings easy. That means the right sizes, the right durometer, and the right support. Your benefit is fewer leaks, fewer comebacks, and more completed service calls.
Frequently Asked Questions
1. Is this kit suitable for hydraulic service trucks?
Yes. This kit was built for mobile hydraulic repair technicians, service trucks, and repair shops that need common AS568, SAE Boss, and Flange O-Rings ready for field repairs.
2. What is the difference between 70 Duro and 90 Duro O-Rings?
Buna-N 70 Duro is more flexible and commonly used for standard hydraulic sealing. Buna-N 90 Duro is harder and better suited for higher-pressure Boss and Flange fittings where extrusion resistance is important.
3. Can this O-Ring kit be customized?
Yes. We build custom O-Ring kits for customers based on their most-used sizes, applications, and customer demand. Private label and branded kit options are available with a 10-kit minimum.
