• 7.5mm-22.5mm eyepiece focal length 7-22.5mm adjustable magnification = telescope eyepiece focal length. The focal length divided by the superior the eyepiece optical effect, the process of superb quality, is a good choice for astronomers Parameters: [brand]: Vienna Angeleyes [model]: 7.5-22.5mm telescope zoom eyepiece [Focus]: 7.5mm-22.5mm, infinite zoom, no pole change [size]: Standard 1.25 inch /31.7mm telescope general accessories [film]: optical lens, FMC full plating green purple film, high clarity [features]: spiral patch, zoom, HD [application]: Heaven and earth, applicable to all astronomical telescope (31.7mm interface), used to watch the wind The king and the astronomical observation of the surface of the moon, planets, nebulae, star clusters, nebulae and other celestial bodies, the dispersion of high brightness, wide Field, observation is very comfortable; metal mirror body, the whole surface multilayer coating, high quality optical properties. A zoom eyepiece is equivalent to more than one eyepiece, high to low times, short focal to telephoto, the cost is very high, square They regulate multiples, very practical eyepiece. Shock proof box packaging, easy to carry and safe!!