... accuracy and readability down to 1%. A versitle, two scale refractometer designed to measure solutions falling within a range of 0-80%, and ... range selection that can transfer from scale 1 to scale 2 and vice versa being made by a simple rotary control on RHBO ... (never dip the refractometer into the test fluid!), a mini screwdriver for scale calibration, a Users Guide, plus 10 more Extra Pipettes (1 ...