Guan Sheng Optical (GSO - Taiwan) manufacturers the highest quality astronomical mirrors which are designed for use in Astronomical Telescopes.
This is a high quality Parabolic Mirror with a diameter of 114mm, and the focal length is about 900mm
The 4.5" primary miror by GSO is Parabolic quality, aluminized and is coated with a protective film.
The Primary 114mm Astronomical Mirror is Manufactured in Taiwan at the GSO Factory and is suitable for use in personalised Telescope Making or for replacement in your existing 114/900mm Dia Telescope.