Weight per Gallon Cups are used to quickly and accurately determine the weight per gallon, and also the specific gravity of paints, lacquer, pastes, semi-pastes, and other liquid or semi-liquid materials. Until the middle of 1989, GARDCO weight per gallon cups were fabricated using Series 300 Stainless Steel for the sidewall and the easier machined but less corrosion resistant Series 400 Stainless Steel for the base and cover. Now, with the installation of state-of-the-art computer controlled metal cutting machinery, these cups are machined from Series 300 Stainless Steel solid bar stock. Features ; All surfaces are produced to a surface finish better than 32 RMS. ; Internal corners are rounded to a radius of no less than 0.188. in. ; Volume tolerance is within +/- 0.5% of correct theoretical value. ; Volume certification qualifying under ANSI/NCSL Z540-1 or MIL-STD-45662A, as applicable, and conforming to ISO 9000 is available.