Black FKM O-Ring Gasket CS 1.9/3.1/4mm Fluorine Rubber Seal

Black FKM O-Ring Sealing Gaskets – CS 1.9 / 3.1 / 4mm

Keep your machinery, plumbing, and HVAC systems leak-free with these premium FKM (Fluorine Rubber / FPM) O-Ring Sealing Gaskets from Ouling. Available in three cross-section (CS) thicknesses — 1.9mm, 3.1mm, and 4mm — these standard-sized black rubber washers deliver outstanding oil resistance, wear resistance, and temperature resistance for demanding industrial and home applications.

Made in Mainland China.

Why Choose FKM Fluorine Rubber O-Rings?

• Excellent Oil Resistance: FKM compound withstands exposure to fuels, hydraulic fluids, and lubricating oils without swelling or degrading.
• Superior Wear Resistance: Dense rubber construction handles repeated compression cycles, maintaining a reliable seal over time.
• High Temperature Resistance: Performs consistently across a wide temperature range, making it ideal for air conditioning systems, engines, and industrial equipment.
• Standard Dimensions: Wholesale sizing options make these gaskets compatible with a broad range of factory and home fittings.
• Versatile Application: Suitable for factories, workshops, HVAC units, plumbing, and general mechanical assemblies.

Product Specifications

Great Pairings for Your Workshop or Home

If you're stocking up on hardware and maintenance supplies, you might also find these useful:

• 10PCS Stainless Steel Self-Tapping Screws M2.2–M4.8 Phillips – ideal for securing fixtures alongside your sealing components.
• 10pcs Durable Gold Blade Nut Metal Universal Trimmer Accessories – replacement hardware to keep your tools running smoothly.

Learn more: OSHA guidance on hand and power tools

Frequently Asked Questions

Q: What is an FKM O-Ring and where are these FKM fluorine rubber gaskets commonly used?

A: FKM (also known as FPM or Viton®-type) is a high-performance fluorine rubber compound widely used for sealing in applications that involve oils, fuels, chemicals, and elevated temperatures. These black FKM O-ring gaskets are commonly used in HVAC and air conditioning systems, automotive engines, hydraulic systems, industrial machinery, and home plumbing fittings — anywhere a reliable, durable rubber seal is required.

Q: What cross-section (CS) thickness options are available for these O-rings?

A: These sealing gaskets are available in three cross-section thicknesses: 1.9mm, 3.1mm, and 4mm. Selecting the correct CS thickness is important for achieving a proper seal — be sure to measure your groove or fitting before ordering to match the right size.

Q: Are these FKM O-rings suitable for high-temperature environments?

A: Yes. FKM fluorine rubber is specifically chosen for its broad temperature resistance, making these gaskets well-suited for use in high-temperature settings such as air conditioning compressors, engines, and industrial equipment where standard rubber seals may fail.

Q: Can I buy these O-ring gaskets in bulk or wholesale quantities?

A: Yes — these black FKM O-ring sealing gaskets are offered in wholesale specifications, making them an economical choice for factories, maintenance teams, repair workshops, and trade professionals who need reliable seals in multiple sizes.

Production & Packaging Notice

To maintain high stock availability and fast shipping times, our items are sourced from multiple verified manufacturing facilities. While the core quality, materials, and product specifications remain identical, you may notice slight variations in the packaging design, manufacturing origin, or the wording of the printed instructions.