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Zoro Select

Zoro Select O-Ring 3-3/8 in Buna-N Black PK5

SKU CH-XAJN-C16Z9

Pack of five Buna-N O-rings with 3.3 in inside diameter, 0.275 in width, 70A durometer, rated -40 to 250 °F, FDA approved

  • Operates from -40 °F to 250 °F for wide temperature tolerance
  • FDA-approved Buna-N material meets food-contact requirements
  • Metal-detectable design supports contamination-control systems
  • Pack of five ensures spares are on hand
  • Dash number 416 matches standard sizing charts

Ready-to-install Buna-N O-ring kit

This pack contains five black O-rings made from Buna-N rubber rated at 70A durometer. Each ring has a nominal inside diameter of 3 3/8 inches and a 1/4 inch cross-section. The material is FDA approved and operates from -40 to 250 degrees F. They suit maintenance teams needing a small stock of standard dash-416 seals.

Seals 3.3 inch bores with 0.275 inch groove fill

Actual inside diameter measures 3.3 inches while the actual width is 0.275 inches, giving a nominal outside diameter of 3.9 inches. The medium-hard compound resists extrusion in hydraulic and pneumatic glands up to the rated pressure range. Metal-detectable construction helps quality control lines spot contamination. They are not X-ray detectable, so X-ray inspection systems will not see them.

Stable from -40 to 250 degrees F

Buna-N retains flexibility at the low end and resists hardening at the high end without active thermal management. The 70A durometer limits compression set during long dwell times. Power draw and noise are irrelevant for a static elastomer seal. The five-piece pack covers multiple rebuilds or spares for a single maintenance event.

Highlights

  • Operates from -40 °F to 250 °F for wide temperature tolerance
  • FDA-approved Buna-N material meets food-contact requirements
  • Metal-detectable design supports contamination-control systems
  • Pack of five ensures spares are on hand
  • Dash number 416 matches standard sizing charts

Specifications

BrandZORO SELECT

Questions about this item

Will the 3.3 in inside diameter and 0.275 in cross-section fit the grooves on my existing hydraulic cylinders?

The O-ring has an actual inside diameter of 3.3 in and an actual cross-section width of 0.275 in; compare these dimensions to your groove specifications for proper fit.

How can I verify the material hardness is correct once installed?

The Buna-N material carries a 70A durometer rating; a handheld durometer tester can confirm the installed seal matches this medium-hard specification.

Does the pack of five include any lubricant or installation tools, or must I buy them separately?

The package contains five black Buna-N O-rings only; compatible lubricant and installation tools are sold separately.

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