AS568-408 Buna-N 90 Duro Black O-Ring for 2-3/8 ID X 1/4 CS

Buna-N O-Rings 90 Duro Black BN900100-408

$ 1.19 per Each

Minimum Order Quantity (MOQ): 26

Ships within 14 days

Qty	Price
26 - 29	$1.1900
30 - 63	$0.8925
64 - 126	$0.7140
127 - 252	$0.5355
253+	$0.4358

Ordering in large quantities? Ask for a lead time quote — we'll get back to you with pricing and lead time.

Product Details

Material	Buna-N
Temperature Range	-40°F to 250°F
Cross Sectional Shape	Round
Hardness	90
Dash	408
Fractional	ID: 2-3/8 CS: 1/4 OD: 2-7/8
Actual (Inch)	ID: 2.35 ± 0.018 CS: 0.275 ± 0.006 OD: 2.900
Actual (Metric)	ID: 59.69 ± 0.46 CS: 6.99 ± 0.15 OD: 73.670

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.