A twist of the zoom eyepiece housing changes focal length from 21 mm to 7 mm providing a variety of viewing magnification powers; excellent contrast and sharpness making the zoom also of interest for planetary observing
Exceptionally long 16 mm to 33 mm eye relief range allows eyeglass wearers to enjoy the entire view while still wearing their corrective lenses without vignetting; the Zoom eyepiece lets you change magnification power without physically changing eyepieces
Apparent field of view is 30 degree at 21 mm and 43 degree at 7 mm; rubber traction ring ensures a good grip; the 1.25 inch barrel is threaded for filters; actual magnification range will depend on the focal length of your telescope
3X Magnification Precision: Astromania 1.25 inch 3X barlow lens when connected to any 1.25 inch telescope eyepiece; will provide a magnification three times that of the eyepiece; providing a clear planetary observation experience
Advanced Multi-Coated Optics: Premium apochromatic barlow lens with four lens design can easily increase the magnification of the eyepiece; through multi-layer coating; it can capture planetary images with higher contrast and better picture quality