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Black rectangular Buna-N O-rings in a pack of 25

Zoro Select

Zoro Select Square Profile Buna-N O-Ring Dash 135 PK25

SKU CH-PSBN-M7FK9

Pack of 25 Buna-N square-profile O-rings, dash 135, 70A durometer, rated −40 °F to 250 °F

  • Square profile improves sealing in static glands
  • Buna-N material handles -40 to 250 °F
  • 70A durometer balances flexibility and extrusion resistance
  • Pack of 25 covers multiple maintenance jobs
  • Metal-detectable for food-safety line inspections

Square Profile Buna-N O-Ring Pack

This pack contains 25 square-profile Buna-N O-rings in dash 135 size for industrial sealing tasks. The rectangular cross-section suits static glands that need a wider contact surface than round rings provide. Maintenance teams and fluid-system assemblers use them where standard round profiles do not seat reliably.

Installation Notes

Lubricate each ring with compatible grease before pressing it into the groove to avoid twisting the rectangular section. The 0.103 in actual width demands a clean, burr-free gland so the corners seat evenly. Over-stretching during fitting can permanently deform the 70A durometer material and cause leaks.

Pre-Order Checks

Verify the gland dimensions match the 1.9 in actual inside diameter and 2.131 in actual outside diameter before ordering. Confirm the operating temperature stays within the -40 to 250 degrees F range and that the media is compatible with Buna-N. These rings are not FDA compliant and are not X-ray detectable for food or pharma lines.

Highlights

  • Square profile improves sealing in static glands
  • Buna-N material handles -40 to 250 °F
  • 70A durometer balances flexibility and extrusion resistance
  • Pack of 25 covers multiple maintenance jobs
  • Metal-detectable for food-safety line inspections

Specifications

BrandZORO SELECT

Questions about this item

How can I verify the square-profile Buna-N O-ring is sealing correctly after installation?

Check that the 1.9 in inside diameter and .103 in width sit evenly in the groove with no visible gaps; the 70A durometer should compress firmly without extrusion at up to 250 degrees F.

What comes in the PK25 pack and are any additional items required for installation?

The pack contains 25 black Buna-N O-rings dash 135 with a 1 15/16 in nominal inside diameter and 3/32 in nominal width; no extra components are included.

Which dash number and material should I select for a rectangular cross-section seal that operates between -40 and 250 degrees F?

Choose dash 135 Buna-N for the 2.131 in outside diameter and medium-hard 70A durometer suited to that temperature range.

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