AS568-109 Buna-N 70 Duro Black O-Ring for 5/16 ID X 3/32 CS

Buna-N O-Rings 70 Duro Black BN700100-109

$ 0.0372 per Each

Minimum Order Quantity (MOQ): 807

Ships within 7 days

Qty	Price
807 - 940	$0.0372
941 - 2016	$0.0279
2017 - 4031	$0.0223
4033 - 8064	$0.0167
8065 - 16128	$0.0130
16130+	$0.0112

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Product Details

Material	Buna-N
Temperature Range	-40°F to 250°F
Cross Sectional Shape	Round
Hardness	70
Dash	109
Fractional	ID: 5/16 CS: 3/32 OD: 1/2
Actual (Inch)	ID: 0.299 ± 0.005 CS: 0.103 ± 0.003 OD: 0.505
Actual (Metric)	ID: 7.59 ± 0.13 CS: 2.62 ± 0.08 OD: 12.830

Buna-N (Nitrile) O-rings are made from a synthetic rubber copolymer of acrylonitrile (ACN) and butadiene. They are among the most widely used sealing materials due to their excellent resistance to oils, fuels, and many chemicals. Nitrile O-rings provide high mechanical strength, outstanding wear resistance, and good tensile strength, making them ideal for automotive, industrial, and aerospace applications.

Buna-N Recommended Uses

Seals and gaskets, fuel systems, hydraulic systems, oil and gas industry, automotive applications, general-purpose applications.

Buna-N Not Recommended

Brake fluid, ozone, UV exposure, phosphate esters, chlorinated hydrocarbons, aromatic hydrocarbons, ketones, strong acids, atmospheric aging.

Buna-N Limitations

Not suitable for ozone, sunlight, or weathering exposure.
Limited performance in high-temperature environmen.
Not ideal for strong acids and alkalis.
Not recommended for applications requiring low compression set.

Buna-N Usable Temperature Range

-30 to 250°F (-34 to 121°C)

Buna-N Also Known As

Buna-N, Nitrile, NBR, Nitrile Butadiene Rubber.