Starlac Industries manufactures Junior Potentiometer, EE - 551. Starlac Industries is an ISO 9001: 2000 certified manufacturer and exporter of scientific instruments. The Junior Potentiometer has 50cms. Long one resistance wire stretched over a graduated perplex scale. It also has a metallic press button type sliding jockey which can move on a metallic rod along the slide stretched wire. In this Junior Potentiometer 10 resistance coils are linked in series in dial form which can be attached with the stretched wire.