OTC 5025 Diesel Exhaust Fluid Refractometer Kit

The OTC 5025 Refractometer Kit is a portable precision optical instrument used to measure the concentration of Diesel Exhaust Fluid (DEF). This device determines the DEF condition by bending light that passes through a liquid sample on the prism—more concentrated solutions cause greater light bending. The refractometer has a reticle, or scale, which is magnified through the eyepiece for accurate measurement; the defined values on this scale ensure compliance with EPA regulations. Since January 1, 2010, all diesel engines, particularly Class 7-8 trucks equipped with SCR technology, must adhere to regulated NOx emissions standards. Notable manufacturers such as Detroit Diesel (DD13, DD15, DD16), Cummins (ISX line), PACCAR, and Volvo-Mack use SCR systems requiring DEF addition to function optimally. DEF is typically available from truck stops either in bottles or via bulk dispensers located near diesel pumps. Ensuring that the DEF in vehicles is a 32.5% urea/water solution is crucial for proper SCR operation. The kit includes a refractometer, dropper, lens wipe cloth, instructions, quick guide, screwdriver, and a sturdy case for storage and transport, with dimensions of 12.3 x 5.9 x 2.85 inches.