nikon P-400rv显微镜支架螺丝（Nikon P-400rv microscope stand screw），这个电子显微镜停产多年，但是性能依旧，无奈就是支架螺丝丢了买都买不到，索性自己打印一个吧。

The Nikon P-400rv microscope stand screw is hard to find since the microscope has been out of production for many years, but its performance still remains good. Unfortunately, I cannot find a replacement screw to buy, so I decided to print one myself.