Tubular Spring Balance, a series of six color-coded tubular spring scales that can be used for both force and mass measurements. Each is calibrated in both Newtons and grams with a beveled top for use on an inclined plane. The scales incorporate a unique zero adjustment with a clear plastic tube, allowing students to see the action of the spring. Complete with chrome-plated hooks and rings. Length of tube : 160 mm, diam. 20 mm.