8.4MM CS X 189.1MM ID BLACK BUNA 70D

Buna-N O-Ring, 8.4 x 189.1 mm, 70A, Black, -40 to 250°F

Status
Out of Stock
Est. Ship Date
29 Oct 2026
Material
Buna-N (Nitrile / NBR)
Durometer
70 Shore A
Cross Section Type
Round
Color
Black
Minimum Temperature
-40°F (-40°C)
Maximum Temperature
250°F (121°C)
Unit of Measure
EA
SKU:
H8.4X189.1

Product Specification

-
Ordered as H8.4X189.1, this is a black Buna-N (Nitrile) 70 Shore A O-Ring built to an inside diameter of 189.1 mm (7.445 in), a cross section of 8.4 mm (0.331 in), and an outside diameter of 205.9 mm (8.11 in). The o-ring provides a reliable static or dynamic seal by deforming into its gland under assembly load.

Expect good resistance to greases and lubricants, petroleum-based oils, and water. Buna-N (Nitrile) is known for the most widely specified general-purpose sealing elastomer and low compression set under sustained load. Published continuous service range is -40°F (-40°C) to 250°F (121.1°C). It should not be specified for service in automotive brake fluid or ozone and direct sunlight.

Typical settings include fluid power, hydraulic and pneumatic systems, and agricultural equipment.

Stocked as H8.4X189.1 and sold individually. Unit weight is approximately 42.25 g. Confirm chemical compatibility, pressure and temperature against your own application requirements before installing. APG supports cross-referencing from drawings, samples and competitor numbers when a listed size is not an exact fit.
Item
H8.4X189.1
Description
8.4MM CS X 189.1MM ID BLACK BUNA 70D
Actual Outside Diameter
205.9 mm (8.11 inch)
Actual Cross Section
8.4 mm (0.331 inch)
Actual Inside Diameter
189.1 mm (7.445 inch)
FDA Compliant
No
Measurement System
Metric
Metal Detectable
No
NSF Certified
No
Product Code
6015
Product Category
O-Rings - Metric - Commodity