NBR is a polymerizate made of butadiene and acrylonitrile. NBR has good resistance against deformation, abrasion and ozone as well as an excellent oil and petrol resistance.
The resistance against acids is only limited and it is not resistant against solvents. NBR is not weather resistant and the usage in the food area is not recommended.
In the article EPDM vs. NBR you can read a comparison about the two materials.