Professional O-ring manufacturer, this 70 Shore A 25×3.55 hydraulic O-ring is widely used for hydraulic system sealing. Optional materials include NBR, EPDM, FKM, HNBR and VMQ. We have AS568 and other metric sizes in stock. Suitable for hydraulic, pneumatic, automotive and machinery equipment. Custom sizes are available with fast delivery.
Item No :
Lead -0023Brand :
LEADUsage :
Automotive, sanitary, plumbing and water system sealingSize :
70 Shore A ID25xCS3.55MOQ :
50PCS~ 100 pcsLead Time :
7-15 daysPayment :
100% TT, L/C at sigh, Paypal, Wester unionhydraulic rubber O-ring
We supply 70 Shore A & 90 Shore A rubber O-rings for static and dynamic sealing. Multiple material options: NBR, EPDM, FKM, HNBR, VMQ. Both AS568 standard and metric ID×CS sizes are available. Applied in pumps, valves, hydraulic cylinders and general machinery. Stable quality, competitive price and low MOQ
| Item Name | 70 Shore A 25x3.55 hydraulic O-ring |
| Material | Nitrile Butadiene Rubber (NBR / Buna-N) |
| Hardness | 70 ±5 Shore A |
| Color | Black (standard) |
| Manufacturing | Compression molding |
| Size Range | AS568 imperial sizes & metric sizes in stock; custom ID/OD/cross-section |
| Price Tip | The price shown above is just for reference, fnal actual price depends on your design, material request, surface treatment order aty, package request etc. |
| Tolerance | ISO 3601 / AS568 dimensional tolerance |
O-Ring Specific Tolerance Table
This sheet covers dimensional tolerance specifications for both custom molded and standard O‑rings, including inner diameter and cross‑section.
We set tolerance grades in accordance with ISO 3302‑1. For O‑rings with an inner diameter exceeding 670 mm, the tolerance is 0.64% of the inner diameter. Multiple precision classes are available to suit general industrial, hydraulic and high‑demand sealing applications.
All tolerance documentation can be supplied for your incoming inspection, supplier audits and drawing reference. Tighter tolerances can be negotiated for special high‑precision projects
.
We can provide complete physical test reports according to your material requirements, including hardness, tensile strength, elongation, compression set, temperature range and chemical resistance.
We are able to supply COA, COC and compliance documents for REACH, RoHS, FDA and UL. Batch traceability is guaranteed for custom molded sealing parts
Xiamen Lead Rubber & Plastic Industry Co., Ltd. is a professional factory focused on the design and fabrication of rubber & plastic molds, as well as custom molded rubber and plastic components.
We specialize in exporting O-rings, rubber gaskets, various rubber seals, rubber bumpers, molded plastic parts, precision tooling molds and other custom molded products.
Our in-house mold workshop develops custom molds for a wide range of rubber and plastic materials. We design and manufacture tooling strictly according to customers’ 2D/3D drawings, samples and technical specifications.
We provide full one-stop OEM & ODM solutions for global buyers, covering mold development, material formulation, prototyping, mass production and quality inspection. Our products widely serve automotive, hydraulic, pneumatic and general industrial sealing applications.
Custom rubber oring /gasket seal Manufacturing
Lead Rubber is a professional manufacturer specializing in custom molded rubber sealing components and mold fabrication.
We mainly export custom rubber O-rings, gaskets, various rubber seals, rubber bumpers, precision molds and other custom molded rubber & plastic parts.
We develop custom molds for a wide range of rubber and plastic materials based on customers’ drawings, samples and technical requirements. We deliver one-stop OEM & ODM custom sealing solutions for global buyers.
Lead rubber offers full OEM development for custom molded rubber O-rings, gaskets and seals, plus custom plastic components.
Following your drawings, samples or technical specifications, we manufacture tailored sealing parts with our in-house mold workshop covering mold design, CNC machining, trial testing and validation.
We support multiple materials including NBR, EPDM, FKM, Silicone and engineered plastics. Our engineering team collaborates with you for prototype sampling and mass production tooling to balance quality, lead time and cost.
Lead rubber enforces strict QC throughout rubber O-ring manufacturing, from raw material incoming check to finished goods inspection before shipment.
Our laboratory is equipped with hardness tester, projector, micrometer, compression set tester and tensile tester. We conduct visual inspection, dimensional measurement, Shore A hardness, compression set and tensile strength tests.
Material certificates and batch inspection reports are available upon request to guarantee consistent sealing performance.
Lead Rubber offers packaging options for international shipments, including PE bags, export carton, and palletized packaging where required. Customized packaging, logo printing, and product labeling can be discussed according to order quantity and customer requirements.
Packaging methods are selected according to the product type, shipment method, and destination requirements. Please confirm any special packaging or labeling instructions before placing an order.
Q1: What is this O-ring size?
A1: This O-ring is 70 Shore A, ID 25mm × CS 3.55mm, widely used for hydraulic systems.
Q2: What materials can I choose for this 25×3.55 O-ring?
A2: NBR, EPDM, FKM, HNBR and VMQ are available.
Q3: Is this 25×3.55 O-ring equivalent to AS568 standard?
A3: Yes, it is close to AS568-214, we also have standard AS568 O-rings in stock.
Q4: What is the hardness of this hydraulic O-ring?
A4: Standard hardness is 70 Shore A; 90 Shore A is available for high pressure.
Q5: Where is this 25×3.55 O-ring mainly applied?
A5: It is used for hydraulic cylinders, valves, pumps and other hydraulic equipment sealing.
Q6: Can I get other sizes besides 25×3.55?
A6: Yes, we supply various metric and AS568 sizes, custom sizes are acceptable.
Q7: What payment terms do you accept?
A7: We support T/T, Western Union and Alibaba Trade Assurance. L/C for large orders.
Q8: What is your MOQ?
A8: Low MOQ for stock items. MOQ for custom products depends on material and size.
Q9: How long is the lead time?
A9: Stock goods can be shipped within 1–3 working days. Custom orders take 7–15 working days.
Q10: Do you offer quality inspection before shipment?
A10: Yes, every batch will be inspected before delivery to guarantee stable quality.
Looking for standard or custom rubber O-rings, gaskets and molded rubber seals for automotive & industrial applications? Contact Lead Rubber with your specifications.
Please submit 2D/3D CAD drawings or physical samples, dimensions, rubber material, hardness, quantity, application and special performance requirements for quotation. If custom mold tooling is needed, also advise cavity quantity and mold steel preferences.
Contact Person: Sunny
Tel: 0086-13400616316
WhatsApp: 0086-13400616316
Email: sales1@leadindustryproducts.com
Contact Person: Lucy
Tel: 0086-13328793979
WhatsApp: 0086-13328793979
Email: sales4@leadindustryproducts.com
Contact Person: Nana
Tel: 0086-15872688050
WhatsApp: 0086-15872688050
Email: sales2@leadindustryproducts.com
Pricing Notice: The displayed price is for reference only. The final quotation depends on product design, material selection, dimensions, tooling requirements, order quantity, surface treatment where applicable, and packaging specifications.
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