Rubber 270 Pcs 18 Sizes Kit Air Conditioning O Rings Car Auto Vehicle Repair Tools Air Conditioning Refrigerant Ring. Rubber 270 Pcs 18 Sizes Air Conditioning O Rings Car Auto Vehicle Repair Tools. Hydrogenated Nitrile Butadiene Rubber (HNBR), also known as Highly Saturated Nitrile (HSN) is special class of nitrile rubber (NBR) and is for mission critical applications.
