Mutual Screw & Supply

0.21" CS X 3.725" ID HNBR O-Rings | AS568-343 | Dash 343 | 90 Durometer (8 / Pkg.)

0.21" CS X 3.725" ID HNBR O-Rings | AS568-343 | Dash 343 | 90 Durometer (8 / - Main image
$40.48 $64.26 In stock

HNBR o-rings in AS568-343, 3.725" inner diameter by 0.21" cross-section. Service range -40°F to +300°F (-40°C to +149°C). Also known as HSN, Highly Saturated Nitrile.

Specifications

  • Product type: O-Ring
  • Material: HNBR
  • AS568 dash size: 343
  • Cross-section: 0.21" (5.33 mm)
  • Inner diameter: 3.725" (94.61 mm)
  • Durometer: 90 Shore A
  • Temperature range: -40°F to +300°F (-40°C to +149°C)
  • Measurement type: Imperial
  • Pack quantity: 8 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 ★★★★★

These fit perfectly on my hydraulic cylinder and the 90-durometer feels noticeably more rigid than the standard 70 I was using before. Held up great after a day at 250°F with no visible degradation.

Emily ★★★★★

The 90-durometer hardness on these is no joke—they’re stiff right out of the bag, which is exactly what I needed for a high-pressure seal. They fit the groove perfectly and haven’t budged even with the temp swings between 40°F and 140°F in my setup. Shipping was quick, and the pack of eight felt lik

Grace ★★★★★

I needed an exact 3.725" inner diameter for a hydraulic repair and these HNBR o-rings fit perfectly, with the 90 durometer providing just the right amount of firmness. The -40°F to +300°F service range gives me confidence they'll hold up in both winter and high-heat conditions.