Illuminating element double cross for eyepiece 12.5 mm from our offer. It can be used to highlight the crosshairs of finders, polar ropes, etc., provided they have the same mounting thread (M9 - matches, for example, the Sky-Watcher 9x50 with an illuminated cross) • backlight: LED, red LED • fastening thread: M9 • power supply: 2x AG5 batteries (2 x 1.5 V) • total length: 40 mm