The coatings used on thin film epoxy replicas are suitable for most applications from x-ray to ultraviolet, from visible thru the far infrared. The substrate that the mirror surface is replicated onto determines the thermal stability characteristics of the replica. It is the epoxy itself that limits the replica in the following applications: Very high storage or operating temperatures, Special coatings requiring high temperature deposition, High power CW laser operation, Very high power short pulse laser operation Thermal distortion of ultra-light-weighted optics, Limited spectral transmission range, Typical standard production epoxies are suitable for storage and use at maximum temperatures ranging from 80° to 125°C. Special high temperature epoxies are available for use up to 300°C, but since they must be cured at elevated temperatures, they often do not yield the same precision as the standard production epoxies.