Best Optical Refractometers

HHTEC 4-in-1 antifreeze refractometer ethylene glycol, propylene glycol, for automotive cooling fluid, Windshield washer fluid, AdBlue(DEF), automotive and industrial battery fluid measurement

SunGrow Aquarium Refractometer, 7.6 Inches, Measure Salinity of Water, Remarkable Accuracy, Includes Calibration Tool, Ensures Overall Health of Plant and Marine Life, Easy and Clear Reading

3 in 1 Scale Clinical Refractometer with 10~30°C ATC, Serum Protein 0~12g/dl, Urine Specific Gravity 1.000~1.050, Refractive Index 1.333~1.360 RI for Human Use.

Antifreeze Refractometer for Glycol, Antifreeze, Coolant and Battery Acid. Antifreeze Tester for Measuring Freezing Point of Automobile Antifreeze and Battery Fluid Condition

Salinity Refractometer for Seawater and Marine Fishkeeping Aquarium 0-100 PPT with Automatic Temperature Compensation

High Precision Alcohol Refractometer 0-80% v/v, XRCLIF Hand-held Alcohol Content Measurement Tool, Portable Refractometer Alcohol Meter for Bourbon Vodka Gin Tequila Mezcal Whisky Scotch etc

Laser 7240 Mixture Strength Tester - for Urea (AdBlue®)

Proster Brix Refractometer with ATC Brix 0-80% Hand Held Refractometer with 3 PCS Pipette for Sugar Content Measurement of Sugar Fruit Food Honey etc

Brix Refractometer for Homebrew Beer Wort, RGBS Dual Scale Automatic Temperature Compensation 0-32% Specific Gravity Hydrometer with ATC

Vee Gee Scientific STX-3 Handheld Refractometer, with Salinity Scale, 0-100, -1.0 Accuracy, 1.0 Resolution