Mutual Screw & Supply

0.21" CS X 12.475" ID Buna-N Nitrile O-Rings | AS568-378 | Dash 378 | 70 Durometer | Black (25 / Pkg.)

0.21" CS X 12.475" ID Buna-N Nitrile O-Rings | AS568-378 | Dash 378 | 70 - Main image
$30.49 $50.81 In stock

Buna-N Nitrile o-rings in AS568-378, 12.475" 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: 378
  • Cross-section: 0.21" (5.33 mm)
  • Inner diameter: 12.475" (316.86 mm)
  • Durometer: 70 Shore A
  • Color: Black
  • Temperature range: -40°F to +250°F (-40°C to +121°C)
  • Measurement type: Imperial
  • Pack quantity: 25 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 (4.6 / 5 · 5 reviews)

Samuel C. ★★★★★

I needed a large-diameter o-ring for a water manifold and the 12.475" ID fit perfectly—no leaks. The 70 durometer feels flexible but sturdy, and the 25-pack gives plenty of spares for future projects.

Andrew ★★★★★

Finally got my hydraulic press back in action thanks to these; the 70 durometer is just right for the seal I needed. They slid into the groove perfectly and haven't leaked a drop under 1500 psi.

Eli ★★★★★

The inner diameter measured exactly at 12.475" with my calipers, so these sealed the hydraulic cylinder flange on the first try. The 70 durometer rubber has just enough give to seat into the groove without squishing out of shape.