The King Instrument 7510 / 7511 series rotameter utilizes a float and tapered tube design. As a result, these rotameters have longer and more linear scales, better pointer stability, and 40% greater accuracy than competitively priced products. In addition, the King Instrument 7510 / 7511 series rotameter is precision-machined from durable cast acrylic stock and has 316L stainless steel internal components and fittings (brass fittings optional) .

The King Instrument 7510 / 7511 series rotameter is available in scales ranging from 2 to 10" (50 to 250mm) for increased accuracy and repeatability. Flow capacities range from 7GPH to 20GPM for water and 2.6 SCFH to 60 SCFM for air, with turndown ratios of 10:1 to 12.5:1 unless otherwise indicated .

The maximum temperature rating is 130°F (54°C) for liquid applications and 100°F (38°C) for gas applications. Ambient temperature range is 33 to 125°F (1 to 52°C). The maximum pressure ratings are 125 psig for water and 100 psig for air .