Built for Reliable Sealing Under Pressure
If you are dealing with O-Ring extrusion, seal failure, or inconsistent performance in high-pressure systems, this kit solves that problem fast. The OSK™ Industrial Solid PTFE Back-up Ring Kit is designed to protect your O-Rings, extend service life, and keep your equipment running without leaks or downtime.
This kit includes 325 solid PTFE back-up rings across 36 of the most common AS568 sizes, giving you immediate coverage for maintenance, repair, and production environments. PTFE, also known as Polytetrafluoroethylene, is a high-performance thermoplastic that delivers exceptional chemical resistance, low friction, and stability in extreme temperatures.
For you, that means fewer seal failures, less maintenance, and more confidence every time you install an O-Ring.
Operating Temperature
Operating temperature: -328° to +500°F (–200° to +260°C)
Material & Performance Details
This kit is built using virgin PTFE, a material known for its near-universal chemical compatibility and outstanding performance in demanding environments.
Material: PTFE (Polytetrafluoroethylene)
Color: White
Hardness: Rigid thermoplastic (non-elastomer)
Performance strengths:
- Prevents O-Ring extrusion in high-pressure applications
- Extremely low friction for smoother operation
- Outstanding chemical resistance across aggressive media
- Zero water absorption
- Excellent thermal stability at extreme temperatures
- Extends O-Ring life and improves sealing reliability
Chemical Compatibility:
Excellent resistance to:
- Hydraulic fluids
- Petroleum oils and fuels
- Water and steam
- Acids and alkalis
- Solvents and chemicals
Limited capability with:
- Filled fluorinated compounds under extreme load
Not compatible with:
- Molten alkali metals
- Elemental fluorine at high temperature and pressure
Kit Sizes & Quantities (AS568 Standard)
This kit is structured for real-world use. You get the most commonly used sizes, organized and ready.
- AS568-005 – Qty 15
- AS568-006 – Qty 15
- AS568-007 – Qty 15
- AS568-008 – Qty 15
- AS568-009 – Qty 15
- AS568-010 – Qty 15
- AS568-011 – Qty 15
- AS568-012 – Qty 15
- AS568-013 – Qty 10
- AS568-014 – Qty 10
- AS568-015 – Qty 10
- AS568-016 – Qty 10
- AS568-017 – Qty 10
- AS568-018 – Qty 10
- AS568-110 – Qty 10
- AS568-111 – Qty 10
- AS568-112 – Qty 10
- AS568-113 – Qty 10
- AS568-114 – Qty 10
- AS568-115 – Qty 10
- AS568-116 – Qty 10
- AS568-117 – Qty 5
- AS568-118 – Qty 5
- AS568-119 – Qty 5
- AS568-120 – Qty 5
- AS568-121 – Qty 5
- AS568-210 – Qty 5
- AS568-211 – Qty 5
- AS568-212 – Qty 5
- AS568-213 – Qty 5
- AS568-214 – Qty 5
- AS568-215 – Qty 5
- AS568-216 – Qty 5
- AS568-217 – Qty 5
- AS568-218 – Qty 5
- AS568-219 – Qty 5
Applications & Use Cases
This kit is built for professionals who cannot afford seal failure.
Common applications include:
- Hydraulic systems and cylinders
- Pumps and valves
- Heavy equipment and mobile hydraulics
- Industrial maintenance and repair operations
- Oil and gas equipment
- Chemical processing systems
- Manufacturing and automation equipment
If your system runs pressure, heat, or aggressive chemicals, this kit gives you the protection your O-Rings need to perform consistently.
Key Specifications
- Material: PTFE (Polytetrafluoroethylene)
- Color: White
- Temperature Range: -328°F to +500°F (-200°C to +260°C)
- Pressure Support: Designed to prevent extrusion in high-pressure systems
- Compatibility: Works with standard AS568 O-Rings
- Kit Size: 325 Pieces
- Number of Sizes: 36
Why Buy from The O-Ring Store LLC
When you buy this kit from us, you are not just getting parts. You are getting reliability and support that keeps your operation moving.
- ISO9001:2015 certified quality processes
- USA stock for fast delivery
- Same-day shipping on in-stock items
- Carefully curated size selection based on real customer demand
- Full lot traceability available
- Expert support from a team that understands sealing applications
- Competitive pricing without cutting corners on quality
We focus on making sure you get the right seal solution the first time, because that is what saves you time, money, and frustration.
Frequently Asked Questions
What does a back-up ring do for an O-Ring?
A back-up ring supports the O-Ring and prevents it from extruding into gaps under pressure. This extends seal life and improves performance in high-pressure systems.
Can PTFE back-up rings be used with any O-Ring material?
Yes. PTFE is chemically inert and compatible with nearly all O-Ring materials including Buna-N, Viton, EPDM, and Silicone.
When should I use a back-up ring?
You should use a back-up ring in high-pressure applications, large clearance gaps, or when you want to extend the life and reliability of your O-Ring seal.
