Mutual Screw & Supply

0.139" CS X 5.609" ID Buna-N Nitrile O-Rings | AS568-255 | Dash 255 | 70 Durometer | Black (80 / Pkg.)

0.139" CS X 5.609" ID Buna-N Nitrile O-Rings | AS568-255 | Dash 255 | 70 - Main image
$39.62 $52.83 In stock

Buna-N Nitrile o-rings in AS568-255, 5.609" 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: 255
  • Cross-section: 0.139" (3.53 mm)
  • Inner diameter: 5.609" (142.47 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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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)

Scarlett ★★★★★

The 0.139" cross-section made these o-rings a perfect fit for my hydraulic cylinder rebuild. They seated nicely into the groove and the 70-durometer rubber feels appropriately firm.

Adam ★★★★★

Finally got around to swapping these in for an old worn-out set, and the 70 durometer feel is spot-on for a snug, leak-free fit. The 5.609" ID sits perfectly in the groove I needed, and the -40°F cold rating gives me peace of mind for outdoor gear this winter.

Sophia ★★★★★

The 70 durometer hardness feels just right for these, and the 5.609" ID seats perfectly into the groove without any wrestling. I've got them holding up in a hot oil application around 200°F and they're showing no signs of swelling or hardening after a few weeks.