Focus with Scale The front part focuser with scale for easy and repeatable focusing Lock Ring Locking ring can ensure that the focus position does not change during use Six-point guide ring The six-point fixed method with adjustable angle can adjust the coaxiality between the guide mirror and the main telescope according to the needs; the six screws are equipped with nuts to ensure that the screws will not loosen during use M42 thread T ring is connected by standard M42 thread, suitable for all standard telescope camera SVBONY 12.5mm illuminated eyepiece features double crossline reticle; for accurate polar positioning and long-exposure photo-guiding when using with off-axis guiders for centering and guiding of stars It has access to standard filters and inserts into a standard 1.25-inch zenith mirror. It can proect the eyepiece from dust and moisture. Double crosshair eyepiece Double crosshair design, can easily align the target object. Helps locate and center stars well;also fits for guiding astrophotos when used in off-axis guiders or guide scopes; Notice deviation of the positioning easily;so that guide star and reticle appear in ideal sharpness and definition Brightness Adjustable Adjustable red LED light brightness control to illuminate crosshairs and preserve night vision, you can twist the knob to meet your different requirement. Fully coated anti reflection coatings Multi-coated 4-elements Plossl design - excellent color correction and sharpness, provide bright views with a 40-deg apparent field of view