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-438 BLACK BUNA 50D O-RING

Buna-N O-Ring, 6.225 in ID x 0.275 CS, 50A, Black, -40 to 250°F

Status
Out of Stock
Est. Ship Date
21 Oct 2026
Material
Buna-N (Nitrile / NBR)
Dash Size
438
Durometer
50 Shore A
Cross Section Type
Round
Color
Black
Minimum Temperature
-40°F (-40°C)
Maximum Temperature
250°F (121°C)
Nominal Cross Section
1/4 inch
Nominal Inside Diameter
6 1/4 inch
Nominal Outside Diameter
6 3/4 inch
Unit of Measure
EA
SKU:
H50438

Product Specification

-
APG stocks the H50438, an AS568-438 black Buna-N (Nitrile) 50 Shore A O-Ring built to an inside diameter of 6.225 in (158.12 mm), a cross section of 0.275 in (6.99 mm), and an outside diameter of 6.775 in (172.09 mm). An o-ring seats in a machined groove and forms a leak-tight barrier when compressed between two mating surfaces.

Expect good resistance to hydraulic fluids, propane and butane, and greases and lubricants. Buna-N (Nitrile) is valued for the most widely specified general-purpose sealing elastomer and low compression set under sustained load. Continuous operating temperature is published at -40°F (-40°C) to 250°F (121.1°C). It should not be specified for service in strong acids or polar solvents.

It sees regular use in fluid power, construction equipment, and general industrial maintenance.

H50438 ships individually. As always, verify media compatibility and operating conditions against the requirements of your specific application.
Item
H50438
Description
-438 BLACK BUNA 50D O-RING
Actual Cross Section
0.275 inch (6.99 mm)
Actual Inside Diameter
6.225 inch (158.12 mm)
Actual Outside Diameter
6.775 inch (172.09 mm)
FDA Compliant
No
Measurement System
Imperial
Metal Detectable
No
NSF Certified
No
Product Code
6005
Product Category
O-Rings - Bulk - Commodity