Simply screw the MAGNA VIEW 1.6x supplementary lens unit threads directly onto the nosepiece of any 1.25" imported eyepiece having a standard filter thread or a camera nosepiece barrel and boost magnification by 60 percent. Adding only 13mm to the length of the original eyepiece. This lens system is a twin lens construction and is fully multi-coated. Ideally use with any of our imported eyepiece, web cams and CCTV