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Hydraulic Boss O-Rings

Hydraulic Boss O-Rings for use with Hydraulic tube fittings.

There is 20 standard sizes for O-rings used to seal straight-thread tube fittings on a boss. A boss Tube fitting with boss seal is cylindrical projection on a casting or forging. The end of that projection is machined to provide a flat, smooth surface for sealing. Straight threads used with an O-ring provide a better seal than tapered threads used alone. Although made in a variety of o-ring compounds the most common Boss O-rings are Buna-N in 90 Durometer.

The 900 series of dash numbers identifies the 20 sizes of boss seals. Except for size -901, the digits after the 9 identify the nominal tube size in 16ths of an inch. The tube size is its outside diameter (OD). For example, size -903 is intended for use with 3/16-inch tube. The one exception, size -901, is intended for use with 3/32-inch tube. 1/16-inch tube is not common in aircraft use.

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The O-Ring Store LLC, We make getting o-rings easy!!

The O-Ring Store LLC began in 2007 supplying O-Rings primarily to the large Paintball industry including our own shop and field. Over the last decade we have been fortunate enough to supply O-Rings and Hydraulic Seals to tens of thousands of customers in every industry. The crew is comprised of friends and family that work hard for each other and everyone that relies us to be their O-Ring supplier. Outside a select few, the big O-Ring brand service levels have became counterproductive to real customer service so we have been developing a network of partners with unique capabilities that allow us to provide a multitude of products, materials, and production capabilities to ensure our customers receive the best product and service options possible. This has allowed us our own line of branded materials which utilize the same raw polymers and contract manufacturers as the big brands, but without the overhead, complications and attitudes that result in high prices in lead times. Currently we stock over 50,000,000 O-Rings and Seals . Due to customer requests and to better our processes, we have begun the process to be ISO 9001 Certified in the first quarter 2020. It has been and will continue to be a wonderful journey with challenges and rewards. Thank you for your support and confidence.

Proud to be an Authorized Freudenberg Sealing Technologies Distributor! Expanding our Mil-Spec, Aerospace and Chemical Resistant O-Rings to new Extremes.

Freudenberg NOK Sealing Technologies is a leading manufacturer in Europe and America for various types of industrial seals, o-rings, piston seals, and shaft seals. The company’s sealing products are well-known for their cost saving benefits such as superior speed, efficiency, quality, and flexibility. Freudenberg provides solution driven products by using global processes and world-class manufacturing methodologies.