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-251 BLACK BUNA 70D O-RING

Buna-N O-Ring, 5.109 in ID x 0.139 CS, 70A, Black, Metal Det., -40 to 250°F

Status
Out of Stock
Est. Ship Date
21 Mar 2027
Material
Buna-N (Nitrile / NBR)
Dash Size
251
Durometer
70 Shore A
Cross Section Type
Round
Color
Black
Minimum Temperature
-40°F (-40°C)
Maximum Temperature
250°F (121°C)
Nominal Cross Section
1/8 inch
Nominal Inside Diameter
5 1/8 inch
Nominal Outside Diameter
5 3/8 inch
Unit of Measure
EA
SKU:
H70MD251

Product Specification

-
The H70MD251 is an AS568-251 black Buna-N (Nitrile) 70 Shore A O-Ring built to an inside diameter of 5.109 in (129.77 mm), a cross section of 0.139 in (3.53 mm), and an outside diameter of 5.387 in (136.83 mm). This o-ring provides a reliable static or dynamic seal by deforming into its gland under assembly load.

Buna-N (Nitrile) is specified here for reliable performance in both static and dynamic service, low compression set under sustained load. It resists greases and lubricants, water, and propane and butane. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). Exposure to strong acids or automotive brake fluid will shorten service life.

The compound is metal detectable for HACCP and foreign-body control programs. It sees regular use in agricultural equipment, automotive, and fluid power.

This item is sold individually under part number H70MD251. Nominal inside diameter is listed as 5 1/8 inch. As always, verify media compatibility and operating conditions against the requirements of your specific application. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.
Item
H70MD251
Description
-251 BLACK BUNA 70D O-RING
Actual Cross Section
0.139 inch (3.53 mm)
Actual Inside Diameter
5.109 inch (129.77 mm)
Actual Outside Diameter
5.387 inch (136.83 mm)
FDA Compliant
No
Measurement System
Imperial
Metal Detectable
Yes
NSF Certified
No
Product Code
6012
Product Category
O-Rings - FDA / Metal Detectable