... be used to process precise grinding & polishing. Power supply: 220V AC, 50Hz.120W. Stepless speed control: 0-12000rpm 2. Portable ... display, voltage & current stabilizer, short circuit protection. Input: 220V AC, 50Hz Output: DC,0-30V, 0-2A 3. Portable metalloscope: The ... 100X-640X. Eyepiece: 10X. Objective: 10X, 25X, 40X. Light source: 6V 15W 4. Microscope photographer: The camera can be connected to ...