Selling brand new Cemax HA optimized 12mm EP by Coronado (enhances solar contrast). This 12mm EP was purchased for use with f/25 hydrogen alpha (solar) filter by mistake (wrong size for my f/25 system). Specifically designed for the faster Coronado HA filters, or other large aperture filters, this eye piece is best suited for use with faster scopes, or high-end non-Coronado systems that can handle the higher powers :-). Selling for $100 shipped (CONUS). Many thanks for consideration!