These instruments are manufactured precisely for achieving better accuracy. Each and every instruments is individually crafted. Borosilicate glass tubes are ground & polished to a high precision internal taper. A float is prepared using anodized aluminium. The tube is then calibrated, using a standard precision master. Markings are made on the glass surface, becoming permanent in the processes of annealing in an electric furnace. The markings on the tubes are then re-checked using another standard master. Besides providing calibrated meter tubes, the instrument set is also provided in an elegant, anodized aluminium/powder-coated frame.