Elastomers of polyepichlorohydrin and poly(epichlorohydrin-ethylene oxide) have been of interest to the automotive and rubber fabricating industry since 1965 because of these polymers balance of properties - oil resistance, ozone resistance, heat resistance and low temperature flexibility.This paper presents and discusses recent studies of 40 day, 125°C. and 150°C. aging of the elastomers in oil and air. Comparison with nitrile rubber under the same conditions is shown.Permeability of the polymers to air, propane nitrogen and Freon is shown at 24°C. and 119°C.The Maxwell Rotating Rod Tester was used to show the effect of temperature on dynamic modulus and loss factor. In addition to the chlorohydrin rubbers EPDM and butyl were studied under the same testing conditions.General suggestions for applications of these polymers are made.