Mutual Screw & Supply

0.21" CS X 3.1" ID Viton FKM O-Rings | AS568-338 | Dash 338 | 75 Durometer | Black (14 / Pkg.)

0.21" CS X 3.1" ID Viton FKM O-Rings | AS568-338 | Dash 338 | 75 Durometer | - Main image
$38.66 $52.24 In stock

Viton FKM o-rings in AS568-338, 3.1" inner diameter by 0.21" cross-section. Service range -15°F to +400°F (-26°C to +204°C). Also known as FKM, Fluoroelastomer.

Specifications

  • Product type: O-Ring
  • Material: Viton FKM
  • AS568 dash size: 338
  • Cross-section: 0.21" (5.33 mm)
  • Inner diameter: 3.1" (78.74 mm)
  • Durometer: 75 Shore A
  • Color: Black
  • Temperature range: -15°F to +400°F (-26°C to +204°C)
  • Measurement type: Imperial
  • Pack quantity: 14 per package
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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 (4.8 / 5 · 5 reviews)

Lucy Y. ★★★★★

The 75 durometer hardness is spot on for my application—firm enough to hold pressure without being a beast to seat. I've got them in a steam line running around 300°F and they're holding up great so far. The 14-pack is a solid value for the price.

Richard ★★★★★

The 3.1" inner diameter fit my flange perfectly, and the 75 durometer hardness feels solid without being stiff. I've got them sitting in hot oil at work and after a week there's zero swelling or deformation. These should last a long time in high-temp service.

Eli B. ★★★★★

I needed o-rings that could handle higher temps for a steam valve repair, and these Viton seals are holding up great at 400°F with no issues. The 75 durometer feels just right—firm but not too stiff to seat properly.