Automotive nitrile hoses that have been produced to withstand temperatures up to 125°C at a relatively low cost have been examined. Special compounding techniques and hose fabrication developments have been reviewed which increase the service limit of nitrile hose to 135°C. Higher acrylonitrile polymers appear to be better suited to meet the more stringent sour gas, permeability, and possible heat resistance required in today's hose market. However, low temperature properties will suffer. If further improvements in heat resistance are going to be required, hydrogenated nitriles or speciality elastomers are going to be needed at a substantial cost increase.