Nitrile FDA O-rings are a type of rubber seal that are made from a material called nitrile butadiene rubber (NBR). These O-rings are specifically designed to meet the requirements set by the US Food and Drug Administration (FDA) for use in food and medical applications. They are resistant to oils, fuels, and other chemicals, and have a temperature range of -40°F to 250°F. They are also highly durable and resistant to wear, making them a great choice for applications where a long service life is needed. Due to their FDA certification, they are safe to use in contact with food and pharmaceuticals.