[6187]89ED Basic OTA Set Part # 6187 Description 89ED Basic OTA Set Aperture 89mm ED Focal length 600mm F-ratio 6.7 Lens configuration 2 elements in 2 groups Coating Fully multi-coated Physical length 470mm Tube diameter 80mm Weight 2.1kg Filter 82mm (front cap) Parts included 2589, 6003 & 7000 Notes