Mutual Screw & Supply

0.139" CS X 4.859" ID Buna-N Nitrile O-Rings | AS568-249 | Dash 249 | 70 Durometer | Black (80 / Pkg.)

0.139" CS X 4.859" ID Buna-N Nitrile O-Rings | AS568-249 | Dash 249 | 70 - Main image
$30.55 $50.09 In stock

Buna-N Nitrile o-rings in AS568-249, 4.859" 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: 249
  • Cross-section: 0.139" (3.53 mm)
  • Inner diameter: 4.859" (123.42 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)

Timothy ★★★★★

I was worried about finding the right o-ring for a high-temp seal repair, but the 70 durometer Buna-N material handles the heat exactly as needed. The 4.859" ID sits snug in the groove, and the 0.139" cross-section gives a firm, even seal.

Owen W. ★★★★★

The 4.859" inner diameter was a perfect fit for my industrial hydraulic cylinder, and the 70 durometer feels just right for the pressure I'm running. These Buna-N rings handle the heat from my compressor setup without any issue, and the 80-pack means I've got spares for future repairs.

Robert ★★★★★

Had to replace a worn seal on my hydraulic cylinder and these Buna-N rings were exactly what I needed—the 70 durometer feels nice and firm for a tight fit. Worked right out of the pack with no issues, and the price for an 80-pack is hard to beat.