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Learn more about Hi-Tech Seals, our core values, and our commitment to delivering effective sealing solutions to our customers.
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With decades of experience, technical expertise, and in-house capabilities, we deliver sealing solutions tailored to customer applications across diverse markets.
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WolCar™ Carbide
KasPex™ PEEK
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WolCar™ Carbide
Superior-performing cemented tungsten carbide materials offering extreme toughness, hardness, and exceptional wear resistance for high-stress environments. WolCar™ can be manufactured into virtually any shape and size to suit specific applications. 
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KasPex™ PEEK
High-performance thermoplastic PEEK materials designed for demanding applications that require outstanding mechanical strength and chemical resistance, even at high temperatures. They enhance the performance and reliability of machined parts in countless applications across numerous markets and industries.  
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TechCera™ Ceramic
Advanced lightweight ceramic materials with excellent mechanical properties and extreme hardness. TechCera™ provides outstanding resistance to chemicals, corrosion, wear, and abrasion, making it ideal for manufacturing precision components that can withstand extreme environments.
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BoKure™ Urethane
BoKure™ urethane is a high‑performance material engineered for demanding industrial conditions. It offers long‑lasting durability and is an excellent alternative to rubber, plastic, and metal in applications where abrasion, impact, and harsh chemicals are a concern.
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BoKure™ GHOST
Degradable elastomer compound formulated to withstand harsh, corrosive downhole oil and gas environments, including aqueous brine conditions. GHOST breaks down into non-binding, non-clogging particles that do not require recovery, eliminating the need for them to be drilled out.
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AraLite™ Compressed Sheet
General-purpose gasket material with high-strength aramid and inorganic fibres reinforced with a nitrile binder. AraLite™ offers outstanding thermal, mechanical, and chemical properties along with high compressibility that enables a tight seal even on irregular surfaces. 
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RyFlor™ ePTFE
Critical service gasket material made from ePTFE that does not degrade or deteriorate even in aggressive chemical and extreme temperature conditions. RyFlor™ has proven success in sealing flanges in demanding environments where leakage could result in serious hazards, supporting safety and reliable operations.  
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Super Hi-Glyde O-Ring Lubricant
FDA-compliant silicone-based lubricant that helps protect seals and speed up the installation process. Super Hi-Glyde™ has high resistance to wear, pressure, rust, and corrosion. It helps protect O-rings and seals from ozone degradation, cracking, abrasion, cutting, and pinching. 
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Engineered to deliver superior protection against contaminants in extremely harsh environments.
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Rapid Seal Machining
Our Rapid Seal machining team can draft, design, and machine standard, replacement, or prototype components. We can also modify standard profile designs to optimize seal performance when necessary. With industry-leading turnaround times, Rapid Seal helps keep projects on track.
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Rapid Gasket delivers precision-cut gaskets for both standard and custom requirements. Using advanced knife-cutting technology, we produce gaskets ranging from simple to complex designs in a variety of materials and thicknesses.
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We manufacture cast urethane products for applications across a wide range of industries. Our team of cast urethane specialists can assist with the design, development, and production of both simple and complex components using our BoKure™ family of urethane compounds.
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Spliced & Vulcanized O-Rings
Our Spliced & Vulcanized O-Rings are a preferred choice for static applications, offering an ideal solution for customers with unique size requirements or those needing small quantities without long lead times.
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We specialize in custom-moulded solutions for diverse applications, creating high-performance products through a collaborative process from design to production. With our experience and capabilities, we deliver high-quality parts tailored to specific requirements.
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Hi-Tech Seals offers a range of standard and custom extruded rubber profiles. We work with customers to deliver the profile configuration and material combination that best meets the demands of the application.
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We consolidate O-rings, industrial seals, and related components into custom seal kits built to match specific cylinder and equipment configurations, reducing rebuild time and simplifying parts sourcing across multiple applications such as hydraulic, pneumatic, valve, and more.
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Laser engraving adds identification marks to rubber, plastic, and metal parts. These marks improve product identification, enhance traceability, strengthen branding, and make reordering easier.
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Customers ask to have their PTFE O-Rings coloured for quick and easy identification once the O-rings have been installed into their application to see differences between sizes and or materials.
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The VMI program maintains optimal inventory levels through regular checks, a min/max system, and timely replenishment. This reduces safety stock requirements, eliminates usage logging and manual checks, and saves procurement time.
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Use our Size Charts to find standard O-ring dimensions, including inner diameter, outer diameter, and cross-section, in both imperial and metric.
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O-Ring Boss Size Chart | AS568 900-Series ORB Dimensions

O-Ring Boss Size Chart

O-Ring Boss (ORB) refers to a straight-thread fitting connection that uses an O-ring to create the seal. ORB connections are common in hydraulic tubing and fitting assemblies, where the seal is formed by O-ring compression rather than tapered threads.

This O-Ring Boss size chart lists standard AS568 900-series O-rings used as boss gaskets for straight thread tube fittings. The chart compares AS568 dash numbers, tube outside diameter (O.D.), O-ring inside diameter (I.D.), cross-section (C/S), and tolerances in both imperial and metric, alongside Hydraulic MIL-P-5570 / MS28778 reference numbers.

Dash #	Tube Size (O.D.) Inch	Hydraulic MIL-P-5570/ MS28778	Imperial Actual (Inches)				Metric Actual (MM)
Dash #	Tube Size (O.D.) Inch	Hydraulic MIL-P-5570/ MS28778	I.D.	± TOL	C/S	± TOL	I.D.	± TOL	C/S	± TOL
901	3/32		0.185	±0.005	0.056	±0.003	4.70	±0.13	1.42	±0.08
902	1/8	2	0.239	±0.005	0.064	±0.003	6.07	±0.13	1.63	±0.08
903	3/16	3	0.301	±0.005	0.064	±0.003	7.65	±0.13	1.63	±0.08
904	1/4	4	0.351	±0.005	0.072	±0.003	8.92	±0.13	1.83	±0.08
905	5/16	5	0.414	±0.005	0.072	±0.003	10.52	±0.13	1.83	±0.08
906	3/8	6	0.468	±0.005	0.078	±0.003	11.89	±0.13	1.98	±0.08
907	7/16		0.530	±0.005	0.082	±0.003	13.46	±0.13	2.08	±0.08
908	1/2	8	0.644	±0.009	0.087	±0.003	16.36	±0.23	2.21	±0.08
909	9/16		0.706	±0.009	0.097	±0.003	17.93	±0.23	2.46	±0.08
910	5/8	10	0.755	±0.009	0.097	±0.003	19.18	±0.23	2.46	±0.08
911	11/16		0.863	±0.009	0.116	±0.004	21.92	±0.23	2.95	±0.10
912	3/4	12	0.924	±0.009	0.116	±0.004	23.47	±0.23	2.95	±0.10
913	13/16		0.986	±0.010	0.116	±0.004	25.04	±0.25	2.95	±0.10
914	7/8	14	1.048	±0.010	0.116	±0.004	26.62	±0.25	2.95	±0.10
916	1	16	1.171	±0.010	0.116	±0.004	29.74	±0.25	2.95	±0.10
918	1‑1/8		1.355	±0.012	0.116	±0.004	34.42	±0.30	2.95	±0.10
920	1‑1/4	20	1.475	±0.014	0.118	±0.004	37.47	±0.36	3.00	±0.10
924	1‑1/2	24	1.720	±0.014	0.118	±0.004	43.69	±0.36	3.00	±0.10
928	1‑3/4	28	2.090	±0.018	0.118	±0.004	53.09	±0.36	3.00	±0.10
932	2	32	2.337	±0.018	0.118	±0.004	59.36	±0.36	3.00	±0.10