S. C. Dey & Co. Supplies Specific Gravity Balance Scale with Rigid A1. Plate. S. C. Dey & Co. Is an ISO 9001 certified company. The Gravity Balance Scale is printed on the vertical plate and a pointer is pivoted in fine bearings for registering sp. Gr. Values. It is available in different ranges like 0.9 to 2.0 graduated 0.01, 2.0 to 2.5 graduated 0.02 and 2.5 to 3.0 graduated 0.05. This Specific Gravity Balance Scale with Rigid A1 Plate is calibrated from 0.9 to 3.0.