Mutual Screw & Supply

0.139" CS X 5.734" ID Buna-N Nitrile O-Rings | AS568-256 | Dash 256 | 70 Durometer | Black (80 / Pkg.)

0.139" CS X 5.734" ID Buna-N Nitrile O-Rings | AS568-256 | Dash 256 | 70 - Main image
$40.03 $53.37 In stock

Buna-N Nitrile o-rings in AS568-256, 5.734" inner diameter by 0.139" 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: 256
  • Cross-section: 0.139" (3.53 mm)
  • Inner diameter: 5.734" (145.64 mm)
  • Durometer: 70 Shore A
  • Color: Black
  • Temperature range: -40°F to +250°F (-40°C to +121°C)
  • Measurement type: Imperial
  • Pack quantity: 80 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)

Zoe T. ★★★★★

The 80-pack is great to have on hand for replacing the worn seals on my hydraulic fittings, and the 70 durometer hardness feels just right for a snug fit. I've used them up to about 200°F so far without any deformation, so the temp range gives me confidence.

Isabella ★★★★★

Fit perfectly on my air compressor quick-connect and stopped the slow leak I’d been dealing with for months. The -40°F to +250°F range gives me confidence these will hold up in my unheated shop.

Alexander ★★★★★

The 70 durometer hardness is exactly what I needed for a snug fit, and the 5.734" inner diameter measured perfectly on the first try. I've got a whole bag left for future projects, which is great since nitrile handles both hot and cold without issue.