SVBONY newest 1.25" red laser collimator includes removable 2" adapter;the triple cemented lens to improve the stability of dot;it's designed for accurate collimation of all Newtonian and SCT reflector telescopes The laser collimator can get better image from the telescope;just insert it into the eyepiece holder;adjust laser beam level;then adjust the telescope screw until the laser beam shoots into the target central Designed for reflector telescope: Fit for standard 1.25" and 2" diameter interface with a 2" adapter Red laser with 7 brightness levels: Adjustable brightness making it easy to use at night and during the day User adjustable collimator: 3 collimation screws on the body to get the laser collimator aligned Triple cemented of Lens: Improve the stability of red dot Much easier aligned process: Watch the collimator from the mirror end of the scope and adjust the screws Quality durable metal materials: Metal material for a long term use. SV165 Mini Guide Scope Support sensitive auto guiding cameras for easy guide star acquisition Getting this guide scope makes sense for most astrophotographers out there. If you're just starting out, SV165 Mini Guide Scope is easy-to-use and performs well. If you're at the other extreme, using SV165 Mini Guide Scope on your smaller imaging rigs is more practical than trying to mount a larger, more exotic guide scope. If portability is important to you, SV165 Mini Guide Scope's compact size and relatively low weight will cooperate with your requirements. Great Fully Multi-Coated optics SV165 Guide Scope Optic Glass is Fully Multi-Coated to eliminate chromatic aberrations and to keep the image crystal clear;Never worry about color fringing or chromatic aberration again.