Brand: Brannan - U.K. Specific Gravity Hydrometer 200 Series 250mm Low Tension 0.80 to 1.00 The specific gravity 60/60°F scale compares the relative density of a given liquid with that of water, at 60°F (15.6°C). The instruments listed are similar to hydrometers included in ISO 650 and in the (now superseded) 1960 issue of British Standard 718.. Product Specifications: Material: Soda glass, Steel shot ballast, Synthetic wax resin Range: 0.200 S60/60°F Accuracy: 0.004 S60/60°F Divisions: 0.002 S60/60°F Overall Length: 250mm Bulb Diameter: 18 - 20mm Approx Weight: 42g (including 11g protective plastic tube)