Refractometer Prism Assembly from Japan
Sapphire prism assemblies for Abbe refractometers (9027.20) that measure refractive index through critical angle optics. These precision-ground prisms provide the optical interface for sample analysis in food, pharmaceutical, and chemical testing. Falls under 9027.90.64.00 as dedicated parts of optical refractometers.
Duty Rate — Japan → United States
12.5%
Rate breakdown
9903.05.4912.5%Except for products described in headings 9903.05.85–9903.05.92, articles the product of Japan, with an ad valorem (or ad valorem equivalent) rate of duty under column 1 less than 12.5 percent, as provided for in U.S. note 52 to this subchapter
Import Tips
• Include calibration certificates showing prism refractive index accuracy to ±0.0001 for proper classification
• Document compatibility with specific refractometer models (e.g
• ABBE type) to distinguish from general optical components
• Avoid bulk packaging that suggests general optical element use, which could trigger 9001 classification