Mutual Screw & Supply

0.21" CS X 18.975" ID Silicone O-Rings | AS568-391 | Dash 391 | FDA Compliant | 70 Durometer | Red (4 / Pkg.)

0.21" CS X 18.975" ID Silicone O-Rings | AS568-391 | Dash 391 | FDA Compliant | - Main image
$37.89 $50.52 In stock

Silicone o-rings in AS568-391, 18.975" inner diameter by 0.21" cross-section. Service range -80°F to +450°F (-62°C to +232°C). Also known as VMQ, Silastic.

Specifications

  • Product type: O-Ring
  • Material: Silicone
  • AS568 dash size: 391
  • Cross-section: 0.21" (5.33 mm)
  • Inner diameter: 18.975" (481.97 mm)
  • Durometer: 70 Shore A
  • Color: Red
  • Temperature range: -80°F to +450°F (-62°C to +232°C)
  • Measurement type: Imperial
  • Compliance: FDA 21 CFR 177.2600
  • Pack quantity: 4 per package
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Standard Shipping: Handling (business days) 0–1; Transit (business days) 7–15.

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 (4.8 / 5 · 5 reviews)

Madison ★★★★★

These have been holding up perfectly in a high-heat application, handling 400°F without any cracking or softening. The 70 durometer feels just right—firm enough to seal but not too stiff to install.

Adam R. ★★★★★

The 0.21" cross-section on these rings is exactly what I needed to reseal a stubborn pipe flange. They slid into place easily and the red color makes them easy to spot during inspection.

Ellie ★★★★★

The high temperature rating of -80°F to +450°F was exactly what I needed for my kiln door seal, and the red silicone is easy to spot during inspection. These 18.975" ID rings seated perfectly without any stretching issues.