The Hanna Checker® bridges the gap between simple chemical test kits and professional instrumentation. Chemical test kits are not very accurate and only give 5 to 10 points resolution while professional instrumentation can cost hundreds of dollars and can be time-consuming to calibrate and maintain. The Checker® is both accurate and affordable.
| Range | 200 to 600 ppm | |
| Resolution | 1 ppm | |
| Accuracy @ 25°C | ±6% of reading | |
| Light Source | light emitting diode @ 610 nm | |
| Light Detector | Silicon Photocell | |
| Environment | 0 to 50 °C (32 to 122 °F); max 95% RH non-condensing | |
| Battery Type | (1) 1.5V AAA | |
| Auto-off | after 10 minutes of non-use | |
| Dimensions | 81.5 x 61 x 37.5 mm (3.2 x 2.4 x 1.5") | |
| Weight | 64 g (2.25 oz.) | |
| Method | adaptation of the zincon method |