Scientific Instrument Traders manufactures supplies and export supreme quality Measuring Equipments for various sorts of lab works. They are designed to standardize the voltmeter with the assistance of a potentiometer. They also assist in the determination of an internal resistance made by the primary cell and the power influence of the A.C. circuit. Additionally, the resistance of a galvanometer can be detected as well. Practical involvement on these set ups proffers a great educative worth for the students of science & engineering. A through study on the study of selenium photo cell is also accomplishable.