Mutual Screw & Supply

0.21" CS X 6.725" ID Buna-N Nitrile O-Rings | AS568-358 | Dash 358 | 70 Durometer | Black (50 / Pkg.)

0.21" CS X 6.725" ID Buna-N Nitrile O-Rings | AS568-358 | Dash 358 | 70 - Main image
$35.98 $58.99 In stock

Buna-N Nitrile o-rings in AS568-358, 6.725" 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: 358
  • Cross-section: 0.21" (5.33 mm)
  • Inner diameter: 6.725" (170.81 mm)
  • Durometer: 70 Shore A
  • Color: Black
  • Temperature range: -40°F to +250°F (-40°C to +121°C)
  • Measurement type: Imperial
  • Pack quantity: 50 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)

Charlotte ★★★★★

The 0.21" cross-section is just right for sealing my old air compressor tank. These o-rings fit perfectly on the filler valve, and the buna-n material feels durable for the heat and pressure. I'll definitely order this pack again when I need more.

David D. ★★★★★

Installed these on a hydraulic cylinder that's been leaking for months — the 70 durometer material sealed it tight on the first try. The dimensions are spot-on to the spec, and at 50 per pack I’ve got plenty of spares for future repairs.

Olivia Y. ★★★★★

Finally, a set of o-rings that actually hold a seal on my hydraulic fittings without leaking after a week. The 70 durometer feels just right for this application, and the 0.21" cross-section fit perfectly into the groove.