Theory:Stereo Microscope Drawtube:Trinocular Theory:Stereo Microscope Drawtube:Trinocular Magnification:7X-45X Eyepieces:10X 20X Objective:0.7 4.5X Base Size:360mm*320mm Working Distance:100mm Usage:PCB Inspection mobile Repair Jewelry inspection ,etc. Light Source:No Light Source