This is a modular stand to hold the XSC G600 electronic microscope or a microscope with holder diameter of 33mm. I designed this because the original stand was terrible.Use 4 x m5 nuts and 4 x m5x30 bolts with hex head to assemble the stand. Important The arm-1.stl (print x 2) and the arm-2.stl (print x 1) parts are different.