Mutual Screw & Supply

0.139" CS X 5.109" ID Viton FKM O-Rings | AS568-251 | Dash 251 | 75 Durometer | Black (16 / Pkg.)

0.139" CS X 5.109" ID Viton FKM O-Rings | AS568-251 | Dash 251 | 75 Durometer | - Main image
$39.17 $55.96 In stock

Viton FKM o-rings in AS568-251, 5.109" inner diameter by 0.139" 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: 251
  • Cross-section: 0.139" (3.53 mm)
  • Inner diameter: 5.109" (129.77 mm)
  • Durometer: 75 Shore A
  • Color: Black
  • Temperature range: -15°F to +400°F (-26°C to +204°C)
  • Measurement type: Imperial
  • Pack quantity: 16 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 (5.0 / 5 · 5 reviews)

Henry P. ★★★★★

Replaced the old Buna-N seals on a steam line that kept failing, and these Viton rings have held up perfectly at 350°F. The 5.109" ID was a dead-on match, no wrestling or stretching to get it seated.

Steven ★★★★★

Finally got the right fit for my high-temp hydraulic seal—the 75 durometer holds up perfectly under pressure without deforming. No leaks after a week of steady 350°F operation.

Lily Y. ★★★★★

These handled the 400°F heat cycling in my compressor without hardening or cracking, which the old Buna ones couldn't manage. The 75 durometer hardness gives them a nice firm feel when seating, and they fit the groove perfectly. Exactly what I needed for a high-temp seal.