AS568-442 Buna-N 70 Duro Black O-Ring for 7-1/4 ID X 1/4 CS

Buna-N O-Rings 70 Duro Black BN700100-442

$ 2.18 per Each

Minimum Order Quantity (MOQ): 14

Ships within 7 days

Qty	Price
14 - 16	$2.1800
17 - 34	$1.6350
35 - 68	$1.3080
69 - 137	$0.9810
138+	$0.8162

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Product Details

Material	Buna-N
Temperature Range	-40°F to 250°F
Cross Sectional Shape	Round
Hardness	70
Dash	442
Fractional	ID: 7-1/4 CS: 1/4 OD: 7-3/4
Actual (Inch)	ID: 7.225 ± 0.045 CS: 0.275 ± 0.006 OD: 7.775
Actual (Metric)	ID: 183.52 ± 1.14 CS: 6.99 ± 0.15 OD: 197.500

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.