Mutual Screw & Supply

Buna-N Nitrile O-Rings | AS568-439 | Dash 439 | 70 Durometer | Black (20 / Pkg.)

Buna-N Nitrile O-Rings | AS568-439 | Dash 439 | 70 Durometer | Black (20 / Pkg.) - Main image
$32.15 $50.24 In stock

Buna-N Nitrile o-rings in AS568-439. 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: 439
  • Durometer: 70 Shore A
  • Color: Black
  • Temperature range: -40°F to +250°F (-40°C to +121°C)
  • Measurement type: Imperial
  • Pack quantity: 20 per package
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When it ships

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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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Delivery costs

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Standard Shipping · United States: $0.00

Express Shipping · United States: $3.99

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Returning an item

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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 (4.6 / 5 · 5 reviews)

Joseph U. ★★★★★

Had to replace the old seals in a coolant system, and these o-rings held up perfectly under the heat after a full day of operation. The material feels durable and hasn't shown any signs of swelling or cracking.

Violet ★★★★★

These fit perfectly on my hydraulic fitting, and the 70 durometer feels firm enough to hold pressure without being hard to install. I've used cheaper o-rings before that cracked in the heat, but these have held up well so far.

Kevin G. ★★★★★

Needed a few of these to replace worn-out seals on a hydraulic fitting, and the -40°F to +250°F range gives me confidence they'll hold up in my unheated garage. The 70 durometer feels just right, not too stiff but not flimsy either.