Mutual Screw & Supply

0.21" CS X 0.537" ID Buna-N Nitrile O-Rings | AS568-311 | Dash 311 | 70 Durometer | Black (400 / Pkg.)

0.21" CS X 0.537" ID Buna-N Nitrile O-Rings | AS568-311 | Dash 311 | 70 - Main image
$38.46 $51.97 In stock

Buna-N Nitrile o-rings in AS568-311, 0.537" 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: 311
  • Cross-section: 0.21" (5.33 mm)
  • Inner diameter: 0.537" (13.64 mm)
  • Durometer: 70 Shore A
  • Color: Black
  • Temperature range: -40°F to +250°F (-40°C to +121°C)
  • Measurement type: Imperial
  • Pack quantity: 400 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)

David ★★★★★

These fit perfectly on the quick-disconnect fittings for my air lines, and the 70 durometer feels plenty firm for the pressure I'm running. The service range down to -40°F is a nice bonus since my workshop isn't heated, and a full 400 pack means I won't need to reorder for a long time.

Emma S. ★★★★★

Had a stubborn leak in the hydraulic line and these 311s sealed it right up. The 70 durometer feels just right for a snug fit, and knowing they handle up to 250°F gives me peace of mind. Solid buy for the price.

Jason A. ★★★★★

The 400-count pack is perfect for stocking up, and the 0.537" inner diameter fit my hydraulic fittings exactly. I’ve been using them in a hot oil system at around 200°F, and they’ve held up without any leaks or hardening so far.