Minor axis: refers to the length of the short side diameter

20mm minor axis auxiliary mirror, the length of the short side is 20mm, the surface is coated with aluminum film and protective film, suitable for use with the 76mm caliber reflective primary mirror.

25mm short axis sub-mirror, the short side length is 25mm, the surface is coated with aluminized film and protective film, suitable for use with the 114mm diameter reflective primary mirror.

35mm minor axis auxiliary mirror, short side length 35mm, surface aluminized film and protective film, suitable for 127mm, 133mm, 135mm, 150mm aperture reflective primary mirror.

40mm minor axis auxiliary mirror, short side length 40mm, surface aluminized film and protective film, suitable for 127mm, 133mm, 135mm, 150mm aperture mirror main mirror.

70mm minor axis secondary mirror, short side length 70mm, surface aluminized film and protective film, suitable for 203mm aperture mirror primary mirror.
Cleaning method: clean the surface of the mirror: first blow off the dust that can be blown away with a blower, then use a high-quality absorbent cotton dipped in alcohol and gently wipe the mirror. After drying, observe the light source from the side to see if there is cotton wool or water stains on it. If necessary, please wipe them gently with a high-quality lens cloth (note, otherwise it will affect the performance of the telescope)