Mutual Screw & Supply

0.21" CS X 17.975" ID Buna-N Nitrile O-Rings | AS568-389 | Dash 389 | 70 Durometer | Black (10 / Pkg.)

0.21" CS X 17.975" ID Buna-N Nitrile O-Rings | AS568-389 | Dash 389 | 70 - Main image
$46.58 $62.1 In stock

Buna-N Nitrile o-rings in AS568-389, 17.975" inner diameter by 0.21" cross-section. Service range -40°F to +250°F (-40°C to +121°C). Also known as NBR, Buna-N, Chemigum, Hycar, Perbunan.

Specifications

  • Product type: O-Ring
  • Material: Buna-N Nitrile
  • AS568 dash size: 389
  • Cross-section: 0.21" (5.33 mm)
  • Inner diameter: 17.975" (456.56 mm)
  • Durometer: 70 Shore A
  • Color: Black
  • Temperature range: -40°F to +250°F (-40°C to +121°C)
  • Measurement type: Imperial
  • Pack quantity: 10 per package
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Standard Shipping: Handling (business days) 0–1; Transit (business days) 7–15.

Express Shipping: Handling (business days) 0–1; Transit (business days) 7–15.

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Standard Shipping · United States: $0.00

Express Shipping · United States: $3.99

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (5.0 / 5 · 5 reviews)

Stella ★★★★★

Used these to replace worn gaskets on a large hydraulic press at the shop, and the 70 durometer feels just like the original spec. The 0.21" cross-section seated perfectly in the groove without any struggle. Exactly what I needed for the job.

Richard ★★★★★

Installed these on a 18-inch industrial drum lid and the fit was spot-on, zero leaks even at 150 psi. The -40°F rating gave me peace of mind for our outdoor equipment in winter.

Violet U. ★★★★★

The 70-durometer feels just right for my hydraulic cylinder seal—not too stiff, not too soft. This 18-inch ring seated perfectly without twisting, and the black Buna-N material handles the heat well. Glad I went with the 10-pack for future projects.